Do you have a question about the M108S and is the answer not in the manual?
Questions and answers
Greg Kaml
March 21, 2025
2017 m108s. When shifting into first or second, tractor kicks out of gear like it's not fully engaging. 3 and 4 work as it should. Is this an adjustment issue or something more. 3200 hrs
2 comments:
Mr. Anderson
March 21, 2025
A Kubota M108S kicking out of gear when shifting into first or second could be due to several possible causes. It may be an adjustment issue, such as improper linkage settings or wear in the shift mechanism. However, it could also indicate a more serious problem, such as worn or damaged gears, synchronizers, or internal transmission components. Checking the shift linkage for proper adjustment and wear is a good first step. If the issue persists, internal transmission inspection may be required.
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TO THE READER This Workshop Manual has been prepared to provide servicing personnel with information on the mechanism, service and maintenance of M108S. It is divided into three parts, “General", “Mechanism” and “Servicing”. General Information on the tractor identification, the general precautions, maintenance check list, check and maintenance and special tools are described.
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M108S, WSM SAFETY INSTRUCTIONS SAFETY INSTRUCTIONS SAFETY FIRST This symbol, the industry’s “Safety Alert Symbol”, is used throughout this manual and on labels on the machine itself to warn of the possibility of personal injury. Read these instructions carefully. It is essential that you read the instructions and safety regulations before you attempt to repair or use this unit.
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M108S, WSM SAFETY INSTRUCTIONS SAFETY STARTING • Do not start the engine by shorting across starter terminals or bypassing the safety start switch. • Do not alter or remove any part of machine safety system. • Before starting the engine, make sure that all shift levers are in neutral positions or in disengaged positions.
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M108S, WSM SAFETY INSTRUCTIONS AVOID FIRES • Fuel is extremely flammable and explosive under certain conditions. Do not smoke or allow flames or sparks in your working area. • To avoid sparks from an accidental short circuit, always disconnect the battery negative cable first and connect it last.
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M108S, WSM SAFETY INSTRUCTIONS PREPARE FOR EMERGENCIES • Keep a first aid kit and fire extinguisher handy at all times. • Keep emergency numbers for doctors, ambulance service, hospital and fire department near your telephone. KiSC issued 06, 2007 A...
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M108S, WSM SAFETY INSTRUCTIONS SAFETY DECALS The following safety decals are installed on the machine. If a decal becomes damaged, illegible or is not on the machine, replace it. The decal part number is listed in the parts list. KiSC issued 06, 2007 A...
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M108S, WSM SPECIFICATIONS SPECIFICATIONS M108S Model Model V3800-CR-TI Type Vertical, water-cooled, 4-cycle diesel engine No. of cylinder Total displacement 3769 cm (230.0 cu.in.) 100 × 120 mm (3.9 x 4.7 in.) Bore and stroke −1 Net power 80.6 kW (108 HP)* / 2600 min...
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M108S, WSM TRAVELING SPEEDS TRAVELING SPEEDS (At rated engine rpm) Model M108S Tire size (Rear) 460 / 85R34 (18.4R34) Transmission type with Dual speed Shuttle shift Range gear shift Main gear shift lever lever lever km/h (mph) km/h (mph) 0.36 (0.22) 0.30 (0.19)
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M108S, WSM TRAVELING SPEEDS (At rated engine rpm) Model M108S Tire size (Rear) 460 / 85R34 (18.4R34) Transmission type with Dual speed Shuttle shift Range gear shift Main gear shift lever lever lever km/h (mph) km/h (mph) 0.36 (0.22) 0.30 (0.19) 0.46 (0.29)
M108S, WSM G GENERAL 1. TRACTOR IDENTIFICATION When contacting your local KUBOTA distributor, always specify engine serial number, tractor serial number and hour meter reading. (1) Tractor Identification Plate (3) CABIN Identification Plate (2) Tractor Serial Number (CABIN Serial Number)
Screws, bolts and nuts should be installed in their original position to prevent reassembly errors. • When special tools are required, use KUBOTA genuine special tools. Special tools which are not frequently used should be made according to the drawings provided.
M108S, WSM G GENERAL 3. HANDLING PRECAUTIONS FOR ELECTRICAL PARTS AND WIRING To ensure safety and prevent damage to the machine and surrounding equipment, heed the following precautions in handling electrical parts and wiring. IMPORTANT • Check electrical wiring damage loosened connection every year.
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M108S, WSM G GENERAL • Securely insert grommet. (1) Grommet (A) Correct (B) Incorrect W1011388 • Securely clamp, being careful not to damage wiring. (1) Clamp (3) Clamp • Wind Clamp Spirally (4) Welding Dent (2) Wire Harness W1011458 • Clamp wiring so that there is no twist, unnecessary sag, or excessive tension, except for movable part, where sag be required.
M108S, WSM G GENERAL [2] BATTERY • Take care not to confuse positive and negative terminal posts. • When removing battery cables, disconnect negative cable first. When installing battery cables, check for polarity and connect positive cable first. • Do not install any battery with capacity other than is specified (Ah).
M108S, WSM G GENERAL • Use sandpaper to remove rust from terminals. • Repair deformed terminal. Make certain there is no terminal being exposed or displaced. (1) Exposed Terminal (3) Sandpaper (2) Deformed Terminal (4) Rust W1012346 • Make certain that there is no female connector being too open.
SAE30, 10W-30 or 15W-40 60.0 L KUBOTA UDT or KUBOTA SUPER Transmission case 63.4 U.S.qts UDT fluid* 52.7 lmp.qts KUBOTA UDT or SUPER UDT fluid* or Turbine oil 32 (see below) [regular type, multipurpose straight 0.3 L mineral oil Brake system 0.32 U.S.qts...
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• Transmission Oil : The oil used to lubricate the transmission is also used as hydraulic fluid. To insure proper operation of the hydraulic system and complete lubrication of the transmission, it is important that a multi-grade transmission fluid be used in this system. We recommend the use of KUBOTA SUPER UDT fluid for optimum protection and performance.
M108S, WSM G GENERAL 5. TIGHTENING TORQUES [1] GENERAL USE SCREWS, BOLTS AND NUTS Screws, bolts, and nuts whose tightening torques are not specified in this Workshop Manual should be tightened according to the table below. Indication on top of...
M108S, WSM G GENERAL [3] HYDRAULIC FITTINGS Hydraulic Hose Fittings Tightening torque Hose size Thread size N·m kgf·m lbf·ft 13.8 to 15.6 1.40 to 1.60 10.2 to 11.5 23 to 27 2.3 to 2.8 17 to 20 46 to 52 4.6 to 5.4...
M108S, WSM G GENERAL 6. MAINTENANCE Indication on hour meter Since Refer- Impor Items then ence -tant 50 100 150 200 250 300 350 400 450 500 550 600 650 700 every page Engine start system Check 50 hrs G-18...
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M108S, WSM G GENERAL Indication on hour meter Since Refer- Impor Items then ence -tant 50 100 150 200 250 300 350 400 450 500 550 600 650 700 every page 18 Water separator Clean G-30 19 Fuel filter Replace...
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• The items listed above (@ marked) are registered as emission related critical parts by KUBOTA in the U.S.EPA nonroad emission regulation. As the engine owner, you are responsible for the performance of the required maintenance on the engine according to the above instruction.
M108S, WSM G GENERAL 7. CHECK AND MAINTENANCE CAUTION • Be sure to check and service the tractor on a flat place with engine shut off, the parking brake on and chock the wheels. [1] DAILY CHECK To prevent trouble from occurring, it is important to know the condition of the tractor. Check the following items before starting.
M108S, WSM G GENERAL [2] CHECK POINTS OF INITIAL 50 HOURS Changing Engine Oil CAUTION • Before changing oil, be sure to stop the engine. • Allow engine to cool down sufficiently, oil can be hot and can burn. 1. To drain the used oil, remove the drain plugs (1) at the bottom of the engine and drain the oil completely into the oil pan.
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2. After draining reinstall the drain plug. 3. Fill with the new KUBOTA SUPER UDT fluid up to the upper notch on the dipstick (2). Refer to “4. LUBRICANTS, FUEL AND COOLANT” in this section.
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M108S, WSM G GENERAL Changing Front Differential Case Oil 1. To drain the used oil, remove the drain and filling plug (1), (3) at the front differential case and drain the oil completely into the oil pan. 2. After draining reinstall the drain plug (1).
M108S, WSM G GENERAL [3] CHECK POINTS OF EVERY 50 HOURS Checking Engine Start System CAUTION • Do not allow anyone near the tractor while testing. • If the tractor does not pass the test, do not operate the tractor.
M108S, WSM G GENERAL [4] CHECK POINTS OF EVERY 100 HOURS Checking Battery Condition CAUTION • Keep electrolyte away from eyes, hands and clothes. If you are spattered with it, wash it away completely with water immediately and get medical attention.
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M108S, WSM G GENERAL Cleaning Air Cleaner Element 1. Remove the air cleaner cover (4) and primary element (2). 2. Clean the primary element if: • When dry dust adheres to the element, blow compressed air from the inside turning the element. Pressure of compressed air must be under 205 kPa (2.1 kgf/cm...
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M108S, WSM G GENERAL Adjusting Fan Belt Tension CAUTION • Be sure to stop the engine before checking belt tension. 1. Stop the engine and remove the key. 2. Apply moderate thumb pressure to belt between pulleys. 3. If tension is incorrect, loosen the alternator mounting bolts and,...
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M108S, WSM G GENERAL 2) Brake Pedal Stroke and Difference between Right and Left Pedal Strokes CAUTION • When checking, park the tractor on flat ground, and stop the engine. 1. Disengage the brake pedal lock. 2. Step on either side brake pedal and measure the level difference (pedal stroke) between right and left pedals.
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M108S, WSM G GENERAL Adjusting Parking Brake Lever Free Play 1. Release the parking brake lever. 2. Pull the parking brake lever with a force of 30.0 kg (66.1 lbs) for checking the free play and check the number of notches.
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M108S, WSM G GENERAL Lubricating Grease Fittings 1. Apply a small amount of multipurpose grease to following points: 2. If you operated the machine in extremely wet and muddy condition, lubricate grease fittings more often. (1) Grease Fitting (Front Axle Support)
M108S, WSM G GENERAL [5] CHECK POINTS OF EVERY 200 HOURS Changing Hydraulic Oil Filter 1. Refer to “[2] CHECK POINTS OF INITIAL 50 HOURS” in this section. W1046442 Checking Radiator Hose and Hose Clamp Check to see if radiator hoses are properly fixed every 200 hours of operation or six months, whichever comes first.
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M108S, WSM G GENERAL Draining Fuel Tank Water 1. Remove the drain plug (2) at the bottom of the fuel tank (1) to left sediments, impurities and water out of the tank. 2. Finally attach the drain plug (2) on the fuel tank (1).
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M108S, WSM G GENERAL Cleaning Inner Air Filter 1. Remove the inner air filter, and blow air the direction opposite to the filter’s normal air flow. Pressure of compressed air must be under 210 kPa (2.1 kgf/cm , 30 psi).
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M108S, WSM G GENERAL Cleaning Fresh Air Filter 1. Remove the knob bolts (3) and pull out filter (1). NOTE • Do not hit the filter. If the filter becomes deformed, dust may enter into the air-conditioner, which may cause damage and malfunction.
M108S, WSM G GENERAL Sliding Air Conditioner Condenser CAUTION • The condenser and receiver become hot while the air conditioner is running. Before checking or cleaning them, wait long enough until they cool down. 1. Release the air conditioner hoses off the hook.
M108S, WSM G GENERAL [7] CHECK POINTS OF EVERY 400 HOURS Cleaning Water Separator 1. Close the fuel cock (1). 2. Unscrew the retainer ring (2) and remove the cup (3), and rinse the inside with kerosene. 3. Take out the element and dip it in the kerosene to rinse.
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M108S, WSM G GENERAL Changing Brake Oil CAUTION • Be sure to check and service the tractor on a flat place with engine shut off and applying the parking brake on. IMPORTANT • Be sure to use the recommended brake oil. (Refer to “4.
M108S, WSM G GENERAL Adjusting King-pin Pivot 1. Jack up the tractor, then loosen the lock nut (2). 2. Measure the adjusting screw tightening torque. 3. If tightening torque is not within the factory specifications, adjust the adjusting screw (1).
M108S, WSM G GENERAL [12] CHECK POINTS OF EVERY 1 YEAR Replacing Air Cleaner Primary and Secondary Element 1. Refer to “[4] CHECK POINTS OF EVERY 100 HOURS” in this section. W1052222 Checking Air Conditioner Pipes and Hoses 1. Check to see that all lines and hose clamps are tight and not damaged.
M108S, WSM G GENERAL [13] CHECK POINTS OF EVERY 2 YEARS Flush Cooling System and Changing Coolant CAUTION • Do not remove the radiator cap when the engine is hot. Then loosen cap slightly to the stop to relieve any excess pressure before removing cap completely.
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M108S, WSM G GENERAL Flush Cooling System and Changing Coolant (Continued) Anti-Freeze CAUTION • When using antifreeze, put on some protection such as rubber gloves (Antifreeze contains position). • If should drink antifreeze, throw up at once and take medical attention.
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The LLC contains anticorrosive agent. If mixed with the cleaning agent, sludge may build up, adversely affecting the engine parts. 7. Kubota's genuine long-life coolant has a service life of 2 years. Be sure to change the coolant every 2 years. NOTE •...
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M108S, WSM G GENERAL Replacing Brake Hose 1. Replace the brake hoses (1). 2. After replacing the hoses, bleed an air from brake system. (Refer to “[14] OTHERS” in this section.) (1) Brake Hose W1054709 Replacing Parking Brake Cable 1. Replace the parking brake cable (3).
M108S, WSM G GENERAL [14] OTHERS Bleeding Fuel System Air must be removed : 1. When the fuel filter or lines ar removed. 2. When water is drained from water separator. 3. When tank is completely empty. 4. After the tractor has not been used for a long period of time.
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M108S, WSM G GENERAL Bleeding Brake System NOTE • While bleeding, make sure to keep enough brake oil in the brake oil reservoir. 1. Disconnect the brake pipes (1) from the master cylinder. 2. Move the brake pedal up and down by hand. At this time, when raising the pedal, close the master cylinder outlet by a finger, and when lowering, release the finger.
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M108S, WSM G GENERAL Replacing Fuse Fuse No. Capacity (Ampere) Protected circuit Meter backup 15 A Flasher (Hazard) 15 A Dome light, Brake lamp 15 A Head light 25 A Auxiliary power 15 A Tail / position lamp, Horn 10 A...
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M108S, WSM G GENERAL Replacing Light Bulb 1. Head lights. Take the bulb out of the light body and replcwith a new one. 2. Other lights Detach the lens and replace the bulb. Light Capacity Head lights 60 / 55 W...
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M108S, WSM G GENERAL Checking the Amount of Refrigerant (Gas) 1. A shortage of refrigerant impairs the air conditioner performance. Check the following points. If it is indicated that the amount of refrigerant is extremely low. Do to inspect and charge.
M108S, WSM G GENERAL 8. SPECIAL TOOLS [1] SPECIAL TOOLS FOR ENGINE Diesel Engine Compression Tester Code No.: 07909-30208 (Assembly) 07909-31251 (G) 07909-30934 (A to F) 07909-31271 (I) 07909-31211 (E and F) 07909-31281 (J) 07909-31231 (H) Application: Use to measure diesel engine compression and diagnostics of need for major overhaul.
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M108S, WSM G GENERAL NOTE • The following special tools are not provided, so make them referring to the figure. Idle Gear Bushing Replacing Tool Application: Use to press out and to press fit the bushing. 1. For idle gear bushing 196 mm (7.72 in.)
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M108S, WSM G GENERAL Valve Guide Replacing Tool Application: Use to press out and press fit the valve guide. 225 mm (8.86 in.) 70 mm (2.8 in.) 45 mm (1.8 in.) 20 mm dia. (0.79 in dia.) 11.7 to 11.9 mm dia. (0.461 to 0.468 in. dia.) 6.50 to 6.60 mm dia.
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M108S, WSM G GENERAL Balancer Bushing Replacing Tool 1 Assembly Application: Use to press fit the bushing. Name of Part Q’ty. Remarks Shaft Piece 1 Piece 2 M6 × P1.0 Bolt W1042867 Balancer Bushing Replacing Tool 1 Components Parts 1) Shaft 498 mm (19.6 in.)
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M108S, WSM G GENERAL 2) Piece 1 Chamfer 0.1 mm (0.004 in.) 1.0 mm (0.039 in.) Chamfer 1.0 mm (0.039 in.) 53.80 to 53.90 mm dia. (2.119 to 2.122 in. dia.) 20.020 to 20.041 mm dia. (0.78819 to 0.78901 in. dia.) 48 mm dia.
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M108S, WSM G GENERAL Balancer Replacing Tools 3, 4, 5 Application: Use to press fit the bushing. NOTE • This special tool is not provided, so make it referring to the figure. Name of Part Q’ty. Bracket Flange Nut Washer...
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M108S, WSM G GENERAL 2) Shaft 44 mm dia. (1.7 in. dia.) 12 mm (0.47 in.) Chamfer 1.0 mm (0.039 in.) 3.0 mm (0.12 in.) 3.0 mm (0.12 in.) 30 mm (1.2 in.) 38 mm (1.5 in.) 35 mm (1.4 in.) M12 ×...
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M108S, WSM G GENERAL 4) Joint 1 M12 × P1.25 Chamfer 1.0 mm (0.039 in.) 30 mm dia. (1.2 in. dia.) 13 mm dia. (0.51 in. dia.) Chamfer 3.0 mm (0.12 in.) 3.0 mm (0.12 in.) 45 mm (1.8 in.) 75 mm (3.0 in.)
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M108S, WSM G GENERAL 7) Piece 3 26 mm (1.0 in.) 18 mm (0.71 in.) 16.5 to 17.0 mm (0.650 to 0.669 in.) 1.5 mm (0.059 in.) 53.00 to 53.20 mm dia. (2.087 to 2.094 in dia.) 49.55 to 49.75 mm dia. (1.951 to 1.958 in dia.) 16 mm (0.63 in.)
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M108S, WSM G GENERAL Engine Stand Application: Use to support engine. 480 mm (18.9 in.) 50 mm (2.0 in.) 108.5 mm (4.272 in.) 262.5 mm (10.33 in.) 12.5 mm (0.492 in.) 237.5 mm (9.350 in.) 142.5 mm (5.610 in.) 95 mm (3.7 in.) 14 mm dia.
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M108S, WSM G GENERAL Injector Adaptor for Measuring Cylinder Compression Pressure Application : Use for measuring diesel engine compression pressure. 16.14 to 16.20 mm dia. (0.6355 to 0.6377 in. dia.) 65 mm (2.6 in.) 29.80 to 30.00 mm dia. (1.174 to 1.181 in. dia.) 102.5 mm (4.035 in.)
M108S, WSM G GENERAL [2] SPECIAL TOOLS FOR TRACTOR Tie-rod End Lifter Code No. : 07909-39051 Application : Use for removing the tie-rod end with ease. W10264720 Steering Wheel Puller Code No. : 07916-51090 Application : Use for removing the steering wheel without damaging the steering shaft.
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M108S, WSM G GENERAL Toe-in Gauge Code No. : 07909-31681 Application : This allows easy measurement of toe-in for all machine models. W10266890 Injector CH3 Code No. : 07916-52501 Application : Use for injecting calcium chloride solution into, and removing it from, rear tires.
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M108S, WSM G GENERAL Shuttle Clutch Compression Tool Code No. : 07916-55031 Application : Use exclusively for pushing the thrust collar, remove the external snap ring. NOTE • Replace the center guide (1) for shown in figure. 20.0 mm dia. (0.787 in. dia.) 11.5 mm dia.
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M108S, WSM G GENERAL Clutch Tool B Code No.: 07916-53041 Application: Use for mounting the clutch to the flywheel. (1) Gauge Ring (No. 07916-53041) (3) Centering Guide (No. 07916-53041) (2) Center Bar (No. 07916-53041) W10520300 Rear Axle Cover Puller Code No. : 07916-51041 Application : Use for removing a rear axle cover from rear axle.
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M108S, WSM G GENERAL NOTE • Special tools for R134a refrigerant air conditioning system introduced below are available from DENSO CO. LTD. Air Conditioner Service Tool Code No.: DENSO.CO. 95048-00061 Application: Use for charging, testing or discharging the air conditioning system.
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M108S, WSM G GENERAL NOTE • The following special tools are not provided, make them referring to the figure. Stopper Magnet Clutch (for A/C Compressor) Application: Use to loosen and tighten the magnet clutch mounting nut. (Use radius M) 125 mm (4.92 in.) 2.09 rad (120 °)
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M108S, WSM G GENERAL NOTE • The following special tools are not provided, so make them referring to the figure. Draft Control Test Bar Application: Use for checking the lift range and floating range of hydraulic draft control. 1045 mm (41.14 in.) 1000 mm (29.37 in.)
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M108S, WSM G GENERAL Valve Adaptor Application : Use for measuring the system pressure of shuttle valve. 24.0 mm (0.945 in.) 27.7 mm (1.09 in.) G1/4 11.0 mm (0.433 in.) 15.0 mm (0.591 in.) 40.0 mm (1.57 in.) 60.0 mm (2.36 in.) 15.0 mm (0.591 in.)
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M108S, WSM G GENERAL Cylinder Safety Valve Setting Pressure Adaptor Application : Use for setting the safety valve to the nozzle tester to measure cracking pressure and check oil tightness of the safety valves. 45.0 mm (1.77 in.) 10.0 mm dia. (0.397 in. dia.) 40.0 mm (1.57 in.)
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M108S, WSM G GENERAL Hydraulic Cylinder Block Tool Application : Use for separating a hydraulic cylinder block. NOTE • The sealing surface of the connecting parts must be welded. 75.0 mm (2.95 in.) 12 mm dia. (0.47 in. dia.) 24.0 mm (0.945 in.) Radius 31.0 mm (1.22 in.
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M108S, WSM G GENERAL Front Axle Rocking Restrictor 120 mm (4.72 in.) 12.0 mm (0.472 in.) M10 × P1.25 30.0 mm (1.18 in.) M16 × P1.5 10 mm (0.39 in.) 20.0 mm (0.787 in.) 36.0 mm (1.42 in.) 64.0 mm (2.52 in.) 45.0 mm (1.77 in.)
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M108S, WSM G GENERAL Clutch Compression Tool Application : Use exclusively for pushing the thrust collar to remove the external snap ring. 60.0 mm (2.36 in.) 120 mm (4.72 in.) M18 × P1.5 screw 45.0 mm (1.77 in.) 115 mm (4.53 in.) 12.0 mm (0.472 in.)
M108S, WSM G GENERAL 9. TIRES [1] TYPE OF TIRES IMPORTANT • Do not use tires larger than specified. Type of Tire Front Rear 9.5L-15 16.9-34 6PR 10.0-16 6PR 18.4-34 Farm Tire 12.4-24 6PR 18.4R36 13.6-24 6PR 18.4-30 13.6R24 18.4R30...
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M108S, WSM G GENERAL 13.6-24 3.6R24 12.4-24 1565 mm (61.61 in.) 1675 mm (65.94 in.) A : Tread NOTE • Need to limit turning angle depended on the tire size. Refer to the chart provided for additional instructions. Front Wheel Steering Angle 1.
M108S, WSM G GENERAL (2) Rear Wheel Adjusting Rear Tread Rear tread width can be adjusted as shown with the standard equipped tires. To change the tread width. 1. Remove the wheel rim and / or disc mounting bolts. 2. Change the position of the rim and / or disc (right and left) to the desired position, and tighten the bolts.
M108S, WSM G GENERAL [3] WHEEL HUB Front wheel hub Rear wheel hub Screw circle diameter 203.2 mm (8 in.) 203.2 mm (8 in.) Number of screws Screws M16 x P1.5 M16 x P1.5 Hub pilot diameter (B) 152.4 mm (6 in.) 152.4 mm (6 in.)
M108S, WSM G GENERAL [5] TIRE LIQUID INJECTION Auxiliary weights can be used to increase traction force for plowing in fields or clayey grounds. Another way is to inject water or another liquid, such as a calcium chloride solution in the tires. Water must not be used in winter since it freezes at 0 °C (32 °F).
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M108S, WSM G GENERAL Attaching Injector 1. Lift the rear tires off the ground. 2. Turn the tire so that the air valve is at the top. 3. Remove the air valve, and attach the injector (Code No. 07916- 52501).
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M108S, WSM G GENERAL Injection CAUTION • When a calcium chloride solution is used, cool it before pouring it into the tire. • Do not fill tires with water or solution more than 75 % of full capacity (to the valve stem level).
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M108S, WSM G GENERAL Draining Water or Solution 1. Lift the rear tires off the ground. 2. Turn the tire so that the air valve is at the bottom. 3. Remove the air valve, and drain liquid (liquid can only be drained to the level of the valve and liquid under that level remains inside).
KUBOTA. Use with implements which are not sold or approved by KUBOTA and which exceed the maximum specifications listed below, or which are otherwise unfit for use with the KUBOTA Tractor may result in malfunctions or failures of the tractor, damage to other property and injury to the operator or others. [Any malfunctions or failures of the tractor resulting from use with improper implements are not covered by the warranty.]...
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M108S, WSM G GENERAL Implement Remarks M108S Max. Tank Capacity 5000 L (1321 U.S.gals, 1100 Imp.gals) Slurry Tank Max. Load Capacity 6000 kg (13200 lbs) Max. Load Capacity 7000 kg (15400 lbs) Trailer Max. Drawbar Load 1500 kg (3300 lbs) Max.
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M108S, WSM G GENERAL Implement Remarks M108S Max. Width 5490 mm (216 in.) Cultivator Number of Rows Max. Weight 900 kg (1980 lbs) Max. Cutting Width 2600 mm (102 in.) Front Blade *1, *2 Max. Oil Pressure 19.6 MPa (200 kgf/cm , 2842 psi) Max.
(PM) contained in their exhaust gas is relatively large, and the emission regulation by the EPA (Environmental Protection Agency) has been gradually strengthened in North America recently. Kubota, which has been positively engaging in the strict emission regulations of the world, has developed the new engine...
M108S, WSM ENGINE 2. ENGINE BODY [1] CYLINDER BLOCK This engine employs separate type crankcases - the crankcase 1 (1) with combustion part and the crankcase 2 (2) which supports the crankcase 1 (1) and reduces noise. Since it is a hanger type, you can easily assemble / disassemble it.
M108S, WSM ENGINE [3] CYLINDER HEAD This engine employs four valve system, the cylinder head is provided with double intake passenge in order to ensure appropriate air suction and give an optimum swirl. (1) Intake (2) Exhaust W1013336 [4] CENTER DIRECT INJECTION SYSTEM (E-CDIS)
M108S, WSM ENGINE [5] PISTON Piston’s skirt is coated with molybdenum disulfide , which reduces the piston slap noise and thus the entire operating noise. Molybdenum disulfide (MoS The molybdenum disulfied serves as a solid lubricant, like a Graphite or Teflon. This material helps resist metal wears even with little lube oil.
M108S, WSM ENGINE 3. LUBRICATING SYSTEM [1] OIL COOLER V3 series engine has a water-cooled oil cooler that not only cools hot oil, but also warms the cool engine oil shoftly after start up. As shown in the figure, the oil flows inside the...
M108S, WSM ENGINE 4. COOLING SYSTEM [1] THERMOSTAT Conventional thermostatically-controlled valves (outlet water temperature control type) open against the flow of coolant. In this design, the pressure (steam pressure + water pump’s discharge pressure) affects the open/close performance of such valve. In other words,...
M108S, WSM ENGINE [2] BOTTOM BYPASS SYSTEM Bottom bypass system is introduced in V3 series for improving the cooling performance of the radiator. While the temperature of coolant in the engine is low, the thermostat is held closed and the coolant is allowed to flow through the bypass pipe and to circulate in the engine.
W1013924 The fuel system of Kubota common rail system diesel engine is shown in the diagram above. Fuel from the tank flows in the passage as shown by the arrows, and is injected from the injector (1) via the supply pump (3) and the rail (2).
M108S, WSM ENGINE 6. INTAKE AND EXHAUST SYSTEM [1] INTAKE AIR HEATER The intake air heater is introduced in order to further improve the starting performance and to reduce the white smoke at cold starting. The intake air heater is mounted on the intake manifold.
M108S, WSM ENGINE [3] INTERCOOLER When the turbocharger (2) compresses the intake air, the air becomes heated (due to compression) and expands. When the heated air expands it becomes less dense. The result is that part of the purpose of the turbocharger is defeated;...
M108S, WSM ENGINE 7. COMMON RAIL SYSTEM (CRS) [1] GENERAL (1) Injector (2) Rail (3) Supply Pump (4) Sensors (5) Engine ECU W1014620 The common rail system adopted for the V3800-CR-TI is the combustion system which always controls the combustion state in cylinders optimally, by storing ultra high pressure fuel in the rail and performing ultra high pressure injection by the diesel engine.
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M108S, WSM ENGINE The common rail control system can be broadly divided into the following three areas : sensors, engine ECU, and actuators. Sensors Sensor detects the condition of the engine and the pump. Refer to “[5] ENGINE CONTROL SYSTEM : (3) Sensors”.
M108S, WSM ENGINE [2] SUPPLY PUMP The supply pump is primarily composed of the pump unit (eccentric cam, ring cam, two plungers), the SCV (suction control valve) (2), the fuel temperature sensor and the feed pump (trochoid type), and is actuated at 1/ 2 the engine crankshaft rotation.
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M108S, WSM ENGINE SCV (Suction Control Valve) (1) Actuating Voltage (2) Current (3) Average Current Difference (4) Plunger (5) Feed Pump (6) Regulating Valve (7) Cylinder (8) SCV A : Low Suction Quantity B : High Suction Quantity C : ON...
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M108S, WSM ENGINE Pump Unit (Eccentric Cam, Ring Cam, Plunger) The eccentric cam (2) is attached to the drive shaft (1) and the ring cam (3) is installed on the eccentric cam (2). There are two plungers (5) at positions symmetrical above and below the ring cam (3).
M108S, WSM ENGINE [3] RAIL The function of the rail (2) is to distribute fuel pressurized by the supply pump to each cylinder injector. The component parts are the pressure limiter (1) and the rail pressure sensor (3). The function of the pressure limiter (1) is to open the valve to release fuel pressure if the fuel pressure in the rail becomes abnormally high.
M108S, WSM ENGINE [4] INJECTOR The injector injects the pressurized fuel in the rail into the engine combustion chamber at the optimal injection timing, injection quantity, injection rate, and injection pattern, in accordance with signals from the engine ECU (Electronic Control Unit) (1).
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M108S, WSM ENGINE Injector Operation (1) Solenoid (2) TWV (Two-Way Valve) (3) Outlet Orifice (4) Command Piston (5) Nozzle (6) Leak Passage (7) Inlet Orifice A : Non Injection B : Injection C : End of Injection D : From Rail...
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M108S, WSM ENGINE Injector Actuation Circuit In order to improve injector responsiveness, the actuation voltage has been changed to high voltage, speeding up both solenoid magnetization and the response of the TWV. The charge circuit in the engine ECU (5) raises each battery voltage to approximately 110V, which is supplied to the injector (1) by signal from the engine ECU (5) to actuate the injector (1).
M108S, WSM ENGINE [5] ENGINE CONTROL SYSTEM (1) Engine Control System Diagram (1) Accelerator Position Sensor (2) Key Switch ON Signal (3) Starter Switch Signal (4) Vehicle Speed Signal (5) Neutral Switch Signal (6) Rail Pressure Sensor (7) Rail (8) Pressure Limiter...
M108S, WSM ENGINE (2) Engine ECU (Electronic Control Unit) The engine ECU constantly ascertains the status of the engine through signals from the sensors, calculates fuel injection quantities etc. appropriate to the conditions, actuates the actuators, and controls to keep the engine in an optimal state.
M108S, WSM ENGINE (3) Sensors Crankshaft Position Sensor (Engine Speed Sensor) The crankshaft position sensor (3) is installed near the flywheel pulsar gear (2) on the flywheel (1) and detects the crankshaft angle and outputs the engine speed signal. The sensor unit is a MRE (magnetic resistance element) type.
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M108S, WSM ENGINE Accelerator Position Sensor The accelerator position sensor detects the opening angle of the accelerator pedal and converts the accelerator opening angle into an electric signal and outputs it to the engine ECU. This sensor uses a hall element (2) (5) to generate voltage from change in the direction of the magnetic field.
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M108S, WSM ENGINE Intake Air Temperature Sensor The intake air temperature sensor (A) detects the temperature of the intake air after it has passed the turbocharger. The sensor portion that detects the temperature contains a thermistor (1). The thermistor (1), which has an electrical resistance that changes with temperature, is used to detect the intake air temperature.
D : Coolant Outlet Port W1020494 In order to meet with the strict emission regulations, Kubota has adopted the EGR on the V3800-CR-TI. nitrogen oxide (NOx) which is a hazardous component in exhaust gas is generated by oxidation of nitrogen in the air, due to rise of the combustion temperature in engine combustion chambers.
M108S, WSM ENGINE [3] REED VALVE The reed valve is provided at the confluence of exhaust gas after passing the EGR valve, and intake air. It operates by the pressure difference between inside of the crankcase and the atmosphere, and prevents backflow of the mixture of exhaust gas and intake air generated by the piston and valves.
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SERVICING CONTENTS 1. TROUBLESHOOTING ..................1-S1 2. SERVICING SPECIFICATIONS ..............1-S5 3. TIGHTENING TORQUES ................1-S11 4. CHECKING, DISASSEMBLING AND SERVICING........1-S13 [1] CHECKING AND ADJUSTING [V3800-CR-TI] ........1-S13 (1) Engine Body..................1-S13 (2) Lubricating System ................1-S15 (3) Cooling System.................1-S15 (4) Turbocharger ..................1-S17 [2] SEPARATING ENGINE .................1-S18 (1) Separating Front Axle Support as a Unit ..........1-S18 (2) Separating Engine from Clutch Housing...........1-S23 [3] DISASSEMBLING AND ASSEMBLING [V3800-CR-TI].......1-S25...
M108S, WSM ENGINE 1. TROUBLESHOOTING NOTE • This troubleshooting shows only mechanical failures. Regarding the failures of common rail system (CRS), please refer to the diagnosis manual “COMMON RAIL SYSTEM ENGINE”. Reference Symptom Probable Cause Solution Page Engine Does Not...
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M108S, WSM ENGINE Reference Symptom Probable Cause Solution Page Engine Revolution Is Fuel filter clogged or dirty Replace G-30 Not Smooth Air cleaner clogged Clean or replace G-20 Fuel leak due to loose injection pipe retaining nut Tighten retaining nut...
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M108S, WSM ENGINE Reference Symptom Probable Cause Solution Page Deficient Output Engine’s moving parts seem to be seizing Repair or replace – Supply pump malfunctioning Repair or replace 1-S27 Deficient injection Replace injector 1-S32, 33 Compression leak Check the 1-S13...
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M108S, WSM ENGINE Reference Symptom Probable Cause Solution Page High Oil Pressure Different type of oil Use specified oil Relief valve defective Replace 1-S39 Engine Overheated Engine oil level insufficient Replenish G-15 Fan belt broken or elongated Replace or adjust...
M108S, WSM ENGINE 2. SERVICING SPECIFICATIONS ENGINE BODY Item Factory Specification Allowable Limit Cylinder Head Surface Flatness – 0.05 mm 0.002 in. Top Clearance 0.72 to 0.90 mm – 0.029 to 0.035 in. Compression V3800-CR-TI 3.09 to 3.29 MPa / 2.41 MPa /...
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M108S, WSM ENGINE ENGINE BODY (Continued) Item Factory Specification Allowable Limit Valve Stem to Valve Guide Clearance (Intake) 0.055 to 0.085 mm 0.1 mm 0.0022 to 0.0033 in. 0.004 in. Valve Stem O.D. (Intake) 6.960 to 6.975 mm – 0.2741 to 0.2746 in.
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M108S, WSM ENGINE ENGINE BODY (Continued) Item Factory Specification Allowable Limit Rocker Arm Shaft to Rocker Arm Clearance 0.016 to 0.045 mm 0.15 mm 0.00063 to 0.0017 in. 0.0059 in. Rocker Arm Shaft O.D. 15.973 to 15.984 mm – 0.62886 to 0.62929 in.
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M108S, WSM ENGINE ENGINE BODY (Continued) Item Factory Specification Allowable Limit Timing Gear Idle Gear 1 to Crank Gear Backlash 0.0490 to 0.193 mm 0.22 mm 0.00193 to 0.00759 in. 0.0087 in. Idle Gear 1 to Cam Gear Backlash 0.0490 to 0.189 mm 0.22 mm...
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M108S, WSM ENGINE ENGINE BODY (Continued) Item Factory Specification Allowable Limit Piston Ring Gap Top Ring 0.30 to 0.45 mm 1.25 mm 0.012 to 0.017 in. 0.0492 in. Second Ring 0.30 to 0.45 mm 1.25 mm 0.012 to 0.017 in.
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M108S, WSM ENGINE LUBRICATING SYSTEM Item Factory Specification Allowable Limit Engine Oil Pressure At Idle Speed – 50 kPa 0.5 kgf/cm 7 psi At Rated Speed 200 to 390 kPa 150 kPa 2.0 to 4.0 kgf/cm 1.5 kgf/cm 29 to 56 psi...
M108S, WSM ENGINE 3. TIGHTENING TORQUES Tightening torque of screws, bolts and nuts on the table below are especially specified. (For general screws, bolts and nuts : Refer to “5. TIGHTENING TORQUES” at “G.GENERAL” section.) Item N·m kgf·m lbf·ft Starter's terminal B mounting nut 9.8 to 11...
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M108S, WSM ENGINE [V3800-CR-TI] Item N·m kgf·m lbf·ft Cylinder head cover screw 1 6.87 to 11.2 0.700 to 1.15 5.07 to 8.31 Cylinder head cover screw 2 9.81 to 11.2 1.00 to 1.15 7.24 to 8.31 *Cylinder head screw 98.1 to 107 10.0 to 11.0...
M108S, WSM ENGINE 4. CHECKING, DISASSEMBLING AND SERVICING [1] CHECKING AND ADJUSTING [V3800-CR-TI] (1) Engine Body Compression 1. After warming up the engine, stop it and remove the air cleaner, the muffler, injection pipes, cylinder head covers, overflow pipe, all injectors and all injectors gaskets.
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M108S, WSM ENGINE Checking Valve Clearance IMPORTANT • Valve clearance must be checked and adjusted when engine is cold. 1. Remove the injection pipes, the cylinder head covers, overflow pipe and injectors. 2. Align the TC mark of flywheel and the convex of flywheel housing timing windows so that the first piston (gear case side) comes to the compression top dead center.
M108S, WSM ENGINE (2) Lubricating System Engine Oil Pressure 1. Remove the oil switch and set a pressure tester (Code No. 07916-32032). 2. Start the engine. After warming up, measure the oil pressure of both idling and rated speeds. 3. If the oil pressure is less than the allowable limit, check the following.
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M108S, WSM ENGINE Fan Belt Damage and Wear 1. Check the fan belt for damage. 2. If the fan belt is damaged, replace it. 3. Check if the fan belt is worn and sunk in the pulley groove. 4. If the fan belt is nearly worn out and deeply sunk in the pulley groove, replace it.
M108S, WSM ENGINE Thermostat Valve Opening Temperature 1. Push down the thermostat valve and insert a string between the valve and the valve seat. 2. Place the thermostat and a thermostat in a container with water and gradually heat the water.
M108S, WSM ENGINE [2] SEPARATING ENGINE (1) Separating Front Axle Support as a Unit Draining Coolant CAUTION • Never remove the radiator cap until coolant temperature is well below its boiling point. Then loosen cap slightly to the stop to relieve any excess pressure before removing cap completely.
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M108S, WSM ENGINE Muffler and Bonnet 1. Open the bonnet (2) and disconnect the battery (3) negative terminal and head light 4P connector (7). 2. Remove the bonnet dampers (4) and close the bonnet (2). 3. Remove the bonnet hinge mounting screws (6) through the holes (5) in the upper part of the bonnet.
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M108S, WSM ENGINE Radiator Hoses, Air Cleaner Hoses and Power Steering Hoses 1. Remove the shield weather strip (1). 2. Disconnect the air cleaner hoses (2), (4) from turbocharger. 3. Disconnect the radiator hose (3). 4. Disconnect the power steering hoses (5) from power steering controller.
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M108S, WSM ENGINE Propeller Shaft 1. Slide the propeller shaft cover (3) after removing the screw (5). 2. Tap out the spring pins (2) and then slide the coupling (1) to the rear. (When reassembling) • Apply grease to the splines of the propeller shaft (6) and pinion shaft.
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M108S, WSM ENGINE Air Condenser and Compressor Without discharging the refrigerant from system 1. Remove the air condenser slide stopper (1) and slide out the air condenser (2). 2. Loosen the lock nut (6) and adjusting screw (5) then remove the air compressor belt (8).
M108S, WSM ENGINE Front Axle Support as a Unit 1. Check the front axle and clutch housing case are securely mounted on the disassembling stands. 2. Install the front axle rocking restrictor (1) (refer to “8. SPECIAL TOOLS” at “G. GENERAL” section) to the front axle bracket.
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M108S, WSM ENGINE Separating Engine from Clutch Housing 1. Remove the floor mat (1) and inspection plate (2). 2. Hoist the engine by hoist and chain. 3. Remove the engine mounting screws and nuts, and separate the engine from the clutch housing.
M108S, WSM ENGINE [3] DISASSEMBLING AND ASSEMBLING [V3800-CR-TI] (1) External Components Air Cleaner, Muffler and Others 1. Remove the air cleaner and muffler. 2. Remove the fan, fan belt, alternator and starter. (When reassembling) • Check to see that there are no cracks on the belt surface.
M108S, WSM ENGINE Turbocharger 1. Remove the screw (1), (3). 2. Take off the turbocharger assembly (2). (When reassembling) • Replace the gasket with new one. (1) Screw (3) Screw (2) Turbocharger Assembly W1078106 (3) Exhaust Gas Recirculation (EGR) EGR Cooler and EGR Pipe 1.
M108S, WSM ENGINE (4) Common Rail System (CRS) Supply Pump 1. Set the No. 4 piston at the compression top dead center. NOTE • When setting the No. 4 piston at the compression top dead center, turn the flywheel counterclockwise and align the mark on the flywheel housing (1) and the TC mark on flywheel (2) temporarily.
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M108S, WSM ENGINE Supply Pump (Continued) (When reassembling) • Place the supply pump gear with aligning the timing marks between the supply pump gear and idle gear 2 (white temporary mark). • Replace the O-ring (16) of supply pump with new one.
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M108S, WSM ENGINE Common Rail and Injection Pipes NOTE • Do not loosen the injection pipe retaining nut when the fuel pressure is high. • Do not remove the pressure limiter (5) and the rail pressure sensor (3) from the common rail (2).
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M108S, WSM ENGINE Intake Air Temperature Sensor 1. Remove the intake air temperature sensor (1). (When reassembling) • Replace the gasket with new one. 30 to 39 N·m Intake air temperature Tightening torque 3.0 to 4.0 kgf·m sensor 22 to 28 lbf·ft...
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M108S, WSM ENGINE Crankshaft Position Sensor 1. Remove the crankshaft position sensor mounting screw (2). 2. Remove the crankshaft position sensor (1). (When reassembling) • Replace the O-ring with new one. IMPORTANT • Do not reuse the crankshaft position sensor if you drop the sensor.
M108S, WSM ENGINE (5) Cylinder Head and Valves Cylinder Head Covers and Injectors 1. Remove the coupler (1) from injectors harness (2). 2. Remove the cylinder head cover 2 (3). 3. Mark the injector’s terminal (4) and current lead (5) one side for preventing misconnection.
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M108S, WSM ENGINE Cylinder Head Covers and Injectors (Continued) (When reassembling) • Replace the injectors’ gaskets with new ones. • When you set the injector’s clamp (9), make sure that the steel balls sit on the rocker arm bracket. • Securely tighten the injector’s clamp nuts to the specified torque.
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M108S, WSM ENGINE Rocker Arm and Push Rod 1. Remove the rocker arm (1) as a unit. 2. Remove the push rods (3). 3. Remove the bridge arm (2). (When reassembling) • When putting the push rods (3) onto the tappets (4), check to see if their ends are properly engaged with the grooves.
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M108S, WSM ENGINE Cylinder Head and Tappet 1. Loosen the pipe band, and remove the water return hose (1). 2. Disconnect the fuel hose (2) first and then the fuel filter (3). 3. Remove the IN. / EX. Manifold. 4. Remove the cylinder head screw in the order of (18) to (1), and remove the cylinder head.
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M108S, WSM ENGINE Selecting Cylinder Head Gasket Replacing the Cylinder Head Gasket 1. Make sure to note the notch (a), (b) or (c) of cylinder head gasket (1) in advance. 2. Replace the same notch (a), (b) or (c) as the original cylinder head gasket (1).
M108S, WSM ENGINE (6) Thermostat Thermostat Assembly 1. Remove the thermostat cover mounting screws, and remove the thermostat cover (1). 2. Remove the thermostat assembly (3). (When reassembling) • Apply a liquid gasket (Three Bond 1215 or equivalent) only at the thermostat cover side of the gasket (2).
M108S, WSM ENGINE (8) Water Pump and Oil Cooler Water Pump 1. Remove the pipe band and the water pipe (1). 2. Remove the water pump (2). (When reassembling) • When mounting the water pump, take care not to forget mounting the O-ring and not to let it out of position.
M108S, WSM ENGINE (9) Gear Case and Timing Gears Gear Case Cover 1. Remove the gear case cover. (When reassembling) • Confirm that the liquid gasket coating surface is free of water, dust and oil in order to maintain sealing effect.
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M108S, WSM ENGINE Camshaft and Balancer Shaft 1. Remove the camshaft position pulsar gear (1). 2. Remove the camshaft set screws and draw out the camshaft (2). 3. Remove the balancer shaft 1 set screws and draw out the balancer shaft 1 (3).
M108S, WSM ENGINE Plate (Gear Case) 1. Remove the three plate mounting screws(1). Detach the plate (2). (When reassembling) • Apply Three Bond 1217D adhesive or equivalent over the shaded zones on both sides of the gasket that will be sandwiched between the crankcase and plate.
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M108S, WSM ENGINE Connecting Rod Cap 1. Remove the connecting rod screws (1) from connecting rod cap. 2. Remove the connecting rod caps. (When reassembling) • Align the marks (a) with each other. (Face the marks toward the injection pump.) •...
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M108S, WSM ENGINE Piston Ring and Connecting Rod 1. Remove the piston rings using a piston ring tool. 2. Remove the piston pin (8), and separate the connecting rod (7) from the piston (6). (When reassembling) • Be sure the crankpin bearing and the connecting rod are same I.D.
M108S, WSM ENGINE (11) Flywheel and Crankshaft Flywheel 1. Fix the crankshaft not to turn. 2. Remove the crankshaft position sensor (1). 3. Remove the flywheel screws. 4. Remove the flywheel. NOTE • Do not use an impact wrench. Serious damage will occur.
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M108S, WSM ENGINE Measuring the Gap of Angles between Crankshaft Mechanical Top Dead Center and Crankshaft Position Sensor’s Electrical Top Dead Center 1. Remove the cylinder head covers, injectors, and rocker arm bracket. 2. Set the No. 4 piston at top dead center.
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M108S, WSM ENGINE Measuring the Gap of Angles between Crankshaft Mechanical Top Dead Center and Crankshaft Position Sensor’s Electrical Top Dead Center (Continued) 9. Connect the engine harness (10) and main switch (13). 10.Connect the battery. 11.Set a circuit tester (12) on the output terminal (white lead) and ground terminal (black lead) of crankshaft position sensor (11).
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M108S, WSM ENGINE Flywheel Housing 1. Remove the flywheel housing. (When reassembling) • Apply liquid gasket (Three Bond 1217D or equipment) to flywheel housing. • Confirm that the liquid gasket coating surface is free of water, dust and oil in order to maintain sealing effect.
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M108S, WSM ENGINE Crankcase 1 and Crankcase 2 (When reassembling) • Match the crankcase 1 and 2, referring to the flywheel housing’s contoured face. • Tighten the crankcase 2 mounting screws loosely. • Tighten up the flywheel housing to the specified torque. This helps to minimize the level difference between the crankcase 1 and the crankcase 2 (at the flywheel side).
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M108S, WSM ENGINE Crankshaft 1. Remove the main bearing case. 2. Remove the crankshaft. (When reassembling) • Reassemble the main bearing case having the same number as the one engraved on the crankcase, and set the casting mark “F / W SIDE” on the main bearing case facing towards the flywheel side.
M108S, WSM ENGINE [4] SERVICING (1) Cylinder Head Top Clearance 1. Remove the cylinder head (remove the cylinder head gasket completely). 2. Bring the piston to its top dead center fasten 1.5 mm dia. 5 to 7 mm long fuse wires to 3 to 4 spots on the piston top with grease so as to avoid the intake and exhaust valves and the combustion chamber ports.
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M108S, WSM ENGINE Cylinder Head Flaw 1. Prepare an air spray red check. 2. Clean the surface of the cylinder head with the detergent (2). 3. Spray the cylinder head surface with the red permeative liquid (1). Leave it five to ten minutes after spraying.
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M108S, WSM ENGINE Clearance between Valve Stem and Valve Guide 1. Remove carbon from the valve guide section. 2. Measure the valve stem O.D. with an outside micrometer. 3. Measure the valve guide I.D. of the cylinder head at the most wear part as shown in the figure below with a small hole gauge.
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M108S, WSM ENGINE Correcting Valve and Valve Seat NOTE • Before correcting the valve and seat, check the valve stem and the I.D. of valve guide section, and repair them if necessary. • After correcting the valve seat, be sure to check the valve recessing.
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M108S, WSM ENGINE Free Length and Tilt of Valve Spring 1. Measure the free length (B) with vernier calipers. If the measurement is less than the allowable limit, replace it. 2. Put the spring on a surface plate, place a square on the side of the spring, and check to see if the entire side is contact with the square.
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M108S, WSM ENGINE Push Rod Alignment 1. Place the push rod on V blocks. 2. Measure the push rod alignment. 3. If the measurement exceeds the allowable limit, replace the push rod. 0.25 mm Push rod alignment Allowable limit 0.0098 in.
M108S, WSM ENGINE (2) Timing Gears Timing Gear Backlash 1. Set a dial indicator (lever type) with its tip on the gear tooth. 2. Move the gear to measure the backlash, holding its mating gear. 3. If the backlash exceeds the allowable limit, check the oil clearance of the shafts and the gear.
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M108S, WSM ENGINE Camshaft Alignment 1. Support the camshaft with V block on the surface plate and set a dial indicator with its tip on the intermediate journal at right angle. 2. Rotate the camshaft on the V blocks and get the misalignment (half of the measurement).
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M108S, WSM ENGINE Oil Clearance between Idle Gear Shaft 1, 2 and Idle Gear 1, 2 Bushing 1. Measure the idle gear shaft O.D. with an outside micrometer. 2. Measure the idle gear bushings I.D. with an inside micrometer, and calculate the oil clearance.
M108S, WSM ENGINE Oil Clearance of Balancer Shaft Journal 1. Measure the balancer shaft journal O.D. with an outside micrometer. 2. Measure the cylinder block bore I.D. (A), (B) for balancer shaft with an inside micrometer. 3. If the clearance exceeds the allowable limit, replace the balancer shaft.
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M108S, WSM ENGINE Connecting Rod Alignment NOTE • Since the I.D. of the connecting rod small end bushing is the basis of this check, check the bushing for wear beforehand. 1. Remove the piston pin from the piston. 2. Install the piston pin in the connecting rod.
M108S, WSM ENGINE (4) Crankshaft Crankshaft Side Clearance 1. Set a dial indicator with its tip on the end of the crankshaft. 2. Measure the side clearance by moving the crankshaft to the front and rear. 3. If the measurement exceeds the allowable limit, replace the thrust bearings.
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M108S, WSM ENGINE Oil Clearance between Crankpin and Crankpin Bearing 1. Clean the crankpin and crankpin bearing. 2. Put a strip of plastigage on the center of the crankpin. 3. Install the connecting rod cap and tighten the connecting rod screws to the specified torque, and remove the cap again.
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M108S, WSM ENGINE Oil Clearance between Crankshaft Journal and Crankshaft Bearing 1. Clean the crankshaft journal and crankshaft bearing. 2. Put a strip of press gauge on the center of the journal. IMPORTANT • Never insert the press gauge into the oil hole of the journal.
M108S, WSM ENGINE (5) Cylinder Cylinder Wear 1. Measure the I.D. of the cylinder at the six positions (see figure) with a cylinder gauge to find the maximum and minimum I.D.’s. 2. Get the difference (Maximum wear) between the maximum and the minimum I.D.’s.
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M108S, WSM ENGINE Clearance between Outer Rotor and Pump Body 1. Measure the clearance between the outer rotor and the pump body with a feeler gauge. 2. If the clearance exceeds the allowable limit, replace the oil pump rotor assembly.
M108S, WSM CLUTCH 2. PTO CLUTCH [1] STRUCTURE The PTO shift lever (1) and the PTO clutch valve (3) are connected by the PTO shift cable (2) as shown in the figure. When the PTO shift lever (1) is moved to the B side, the PTO clutch valve (3) is set at “Engaged”...
M108S, WSM CLUTCH [2] OPERATION PTO Valve This valve change the oil flow to PTO clutch. This is rotated by the PTO operation lever via to PTO clutch cable. The oil from the regulator valve passes through orifice (1) and flow to the PTO clutch.
M108S, WSM CLUTCH 2. SERVICING SPECIFICATION TRAVELING CLUTCH Item Factory Specification Allowable Limit Clutch Pedal Free Travel Below 15 mm – 0.59 in. Total Stroke 150 to 155 mm – 5.91 to 6.10 in. Damper Disc Boss to Gear Shaft Backlash –...
M108S, WSM CLUTCH 3. TIGHTENING TORQUES Tightening torques of screws, bolts and nuts on the table below are especially specified. (For general use screws, bolts and nuts : Refer to “5. TIGHTENING TORQUES” at “G.GENERAL” section) Item N·m kgf·m lbf·ft...
M108S, WSM CLUTCH 4. CHECKING, DISASSEMBLING AND SERVICING [1] CHECKING AND ADJUSTING (1) Traveling Clutch Clutch Pedal Stroke 1. Stop the engine and remove the key. 2. Screw the lock nuts (1), (2) to the threaded end of cable as shown in figure.
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M108S, WSM CLUTCH Clutch Pedal Free Travel NOTE • Before checking the clutch pedal free travel A, be sure to adjust the pedal stroke. 1. Measure the clutch pedal free travel. 2. If adjustment is needed, loosen the lock nuts (1) and adjust the cable length within acceptable limits.
M108S, WSM CLUTCH (2) PTO Clutch PTO Clutch Lever Movement 1. Stop the engine and remove the key. 2. Check the PTO clutch lever (1) on the “Engage” and “Disengage” position of PTO clutch lever guide. 3. If the adjustment is needed, loosen the lock nuts (3) and adjust the clutch control cable (2) length.
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M108S, WSM CLUTCH PTO System Pressure 1. Start the engine and warm up the transmission fluid, and then stop the engine. 2. Remove the plug (4) (PT 1/8) on the PTO valve spool (5). 3. Set the adaptor (PT 1/8) (Use the oil pressure tester for diesel engines, Code No.
M108S, WSM CLUTCH [2] DISASSEMBLING AND ASSEMBLING (1) Removing Damper Disc Draining Coolant CAUTION • Never remove the radiator cap until coolant temperature is well below its boiling point. Then loosen cap slightly to the stop to relieve any excess pressure before removing cap completely.
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M108S, WSM CLUTCH Battery and ECU 1. Remove the battery (1). 2. Remove the ECU cover (2). 3. Remove the ECU mounting screws and ECU (3). NOTE • Take care not to damage to ECU. (1) Battery (3) ECU (2) ECU Cover...
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M108S, WSM CLUTCH Differential Lock Spring 1. Loosen the lock nut (1) and disconnect spring (2) from differential lock lever (3). (When reassembling) • Be sure to fix the front edge of differential lock cable at the center of thread.
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M108S, WSM CLUTCH Air Condenser and Compressor Without discharging the refrigerant from system 1. Remove the air condenser slide stopper (1) and slide out the air condenser (2). 2. Loosen the lock nut (6) and adjusting screw (5) then remove the air compressor belt (8).
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M108S, WSM CLUTCH Brake Oil Tank, Joint Shaft and Power Steering Hose 1. Remove the brake oil tank (1). 2. Remove the power steering delivery hose (2). 3. Remove the joint shaft (3). (When reassembling) 22 to 27 N·m Power steering turning Tightening torque 2.2 to 2.8 kgf·m...
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M108S, WSM CLUTCH Separating Engine from Clutch Housing 1. Check the engine and clutch housing case are securely mounted on the disassembling stands. 2. Install the front axle rocking restrictor (1) (refer to “8. SPECIAL TOOLS” at “G. GENERAL” section) to the front axle bracket.
M108S, WSM CLUTCH Damper Disc 1. Remove the damper disc (1). (When reassembling) • Confirm that the bearing (2) is surely assembled to the flywheel. • Direct the shorter end of the damper disc boss toward the flywheel. • Apply molybdenum disulphide (Three Bond 1901 or equivalent) to the shaft A.
M108S, WSM CLUTCH (3) Removing PTO Clutch Valve Gear Pump and Pump Base Assembly 1. Remove the seat (1) and floor cover (2). 2. Remove the floor mat (3) and inspection plate under the floor mat. 3. Remove the delivery pipe 1 (4) and delivery pipe 2 (5).
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M108S, WSM CLUTCH PTO Valve 1. Remove the both hydraulic pumps (1). 2. Remove the cap (2) and internal snap ring (3). 3. Remove the spring pin (4) and then tap out the pin (5). 4. Remove the all gears.
Transmission fluid 63.4 U.S.qts. 52.7 Imp.qts. IMPORTANT • Use only KUBOTA SUPER UDT fluid. Use of other oil may damage the transmission or hydraulic system. • Refer to “4. LUBRICANTS, FUEL AND COOLANT” at “G. GENERAL” section. • Do not mixed different brands fluid together.
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M108S, WSM CLUTCH Fuel Tank and Auxiliary Step 1. Remove the auxiliary steps (1), (2). 2. Disconnect the 2P connector fuel tank unit (3). 3. Disconnect the fuel tank connector hose between left and right side fuel tanks. 4. Remove the fuel tank bands (4).
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M108S, WSM CLUTCH Separating Transmission Case 1. Remove the dual speed HI clutch pipe (4) and LO clutch pipe (5). (DS model only.) 2. Remove the resonator pipe (9). 3. Remove the parking brake cable stay (6). 4. Remove the delivery pipe (8).
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M108S, WSM CLUTCH Rear Cover Assembly 1. Remove the rear cover and PTO drive shaft as a unit. (When reassembling) 78 to 90 N·m Rear cover mounting Tightening torque 7.9 to 9.2 kgf·m screw 58 to 66 lbf·ft W1023232 PTO Clutch Assembly 1.
M108S, WSM CLUTCH [3] SERVICING (1) Damper Disc Backlash between Damper Disc Boss and Shaft 1. Mount the damper disc to the input shaft. 2. Hold the shaft so that it does not turn. 3. Rotate disc lightly and measure the displacement around the disc edge.
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M108S, WSM CLUTCH Flatness of PTO Piston, Return Plate and Plate Assembly 1. Plate the PTO piston (1), return plate (2) and plate assembly (3) on a surface plate. 2. Insert a thickness gauge (allowable limit size) underneath it at least four points.
M108S, WSM TRANSMISSION (2) Operation Shuttle Lever at Neutral Position KiSC issued 06, 2007 A 3-M5...
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M108S, WSM TRANSMISSION (1) Modulating Valve (5) Shuttle Valve A : Check Port (Modulation) T1 to T5: To Transmission Case (2) Proportionally Reducing Valve (6) Inching Valve B : Check Port (Reverse) N1 : Port N1 (3) Shuttle Shift Spool (Forward,...
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M108S, WSM TRANSMISSION When Shuttle Lever is Shifting Neutral to Reverse or Forward Position (Clutch Pedal is Released) KiSC issued 06, 2007 A 3-M7...
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M108S, WSM TRANSMISSION (1) Modulating Valve (5) Shuttle Valve A : Check Port (Modulation) T1 to T5: To Transmission Case (2) Proportionally Reducing Valve (6) Inching Valve B : Check Port (Reverse) N1 : Port N1 (3) Shuttle Shift Spool (Forward,...
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M108S, WSM TRANSMISSION Shuttle Lever at Reverse Position (Clutch Pedal is Released) KiSC issued 06, 2007 A 3-M9...
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M108S, WSM TRANSMISSION (1) Modulating Valve (5) Shuttle Valve A : Check Port (Modulation) T1 to T5: To Transmission Case (2) Proportionally Reducing Valve (6) Inching Valve B : Check Port (Reverse) N1 : Port N1 (3) Shuttle Shift Spool (Forward,...
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M108S, WSM TRANSMISSION Shuttle Lever at Forward Position (Clutch Pedal is Released) KiSC issued 06, 2007 A 3-M11...
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M108S, WSM TRANSMISSION (1) Modulating Valve (5) Shuttle Valve A : Check Port (Modulation) T1 to T5: To Transmission Case (2) Proportionally Reducing Valve (6) Inching Valve B : Check Port (Reverse) N1 : Port N1 (3) Shuttle Shift Spool (Forward,...
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M108S, WSM TRANSMISSION When Clutch Pedal is Depressed (with Shuttle Lever at Reverse or Forward Position) KiSC issued 06, 2007 A 3-M13...
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M108S, WSM TRANSMISSION (1) Modulating Valve (6) Inching Valve D : Check Port (Pump) a : Connect to Shuttle Lever (2) Proportionally Reducing Valve (7) Shuttle Lever F : To Clutch Body (Forward) b : Connect to Clutch Pedal (3) Shuttle Shift Spool (Forward,...
M108S, WSM TRANSMISSION [2] MAIN GEAR SHIFT LEVER Main Gear Shift Lever Linkage 1. 8 speed can be selected by the main gear shift lever (1) and all speeds are fully synchronized to shift without stopping. 2. The main shift rod 1 (2), link arm (6) and main shift rod...
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M108S, WSM TRANSMISSION Shift Fork Rod and Fork (1) 3rd-4th Shift Fork Rod (2) 1st-2nd Shift Fork Rod (3) Shaft (4) 3rd-4th Shift Fork (5) Interlock Ball (6) Detent Ball (7) Safety Switch (8) Spring (9) Cam (10) Select Lever...
M108S, WSM TRANSMISSION [3] SWING SHIFT Operation Method 1. The swing shift is a method which the HI and LO speed range is changing by using the electric and hydraulic device combination. 2. The main gear shift lever is in Neutral position during the engine is running.
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M108S, WSM TRANSMISSION Electrical Device (1) Swing Shift Switch (5) HI Motion Switch A : To Meter Panel (10A Fuse) C : To Meter Panel (2) LO Solenoid Valve (6) Buzzer Relay B : To OPC Unit (Swing Shift HI)
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M108S, WSM TRANSMISSION Hydraulic Device 1. The shift fork rod (1) is used as a double acting piston. 2. The shift fork rod (1) is moved to the right or left by switching the solenoid valve (2), (3) and flowing oil into A chamber (4) or B chamber (5).
M108S, WSM TRANSMISSION [4] DUAL SPEED Dual Speed Model M108S-DS have dual speed device as a standard equipment. The dual speed device consists of the HI-LO clutch, located in the mid case, and the clutch valve that controls the HI-LO clutch.
M108S, WSM TRANSMISSION 4. DUAL SPEED VALVE This valve change the oil flow to the dual speed HI clutch or LO clutch. As the pilot valve DS (4), (5) operates by energizing the solenoid valve (6), the flow of oil is switched to the HI side or LO side of dual speed clutch with DS spool (3).
M108S, WSM TRANSMISSION [2] DUAL SPEED SECTION The dual speed clutch is controlled by the combination of the solenoid valve and the hydraulic flow. When the dual speed shift switch is pushed and indicator comes on, LO speed clutch (4) is engaged.
M108S, WSM TRANSMISSION 6. POWER TRAIN FOR PTO SYSTEM [1] PTO GEAR SECTION PTO system is live PTO (Independent PTO) which has its own clutch controls completely separated from the travelling clutch and transmission. Therefore, the PTO can operate while the tractor is stopped and also the PTO can be disengaged and engaged while the tractor is moving.
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SERVICING CONTENTS 1. TROUBLESHOOTING ..................3-S1 2. SERVICING SPECIFICATIONS ..............3-S3 3. TIGHTENING TORQUES ................3-S5 4. CHECKING AND ADJUSTING ..............3-S6 [1] SHUTTLE LEVER ..................3-S6 (1) Hydraulic Shuttle Model ..............3-S6 (2) Engine Start Condition ................3-S8 [2] MAIN GEAR SHIFT.................3-S9 [3] RANGE SHIFT LEVER .................3-S10 [4] HYDRAULIC SHUTTLE OPERATING PRESSURE ......3-S11 [5] DUAL SPEED / 4WD OPERATING PRESSURE ........3-S13 5.
M108S, WSM TRANSMISSION 1. TROUBLESHOOTING Reference Symptom Probable Cause Solution Page Excessive Transmission fluid insufficient Replenish Transmission Noise Improper backlash between bevel pinion shaft Repair 3-S45 and spiral bevel gear Improper backlash between differential pinion Adjust 3-S48 and side gear...
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M108S, WSM TRANSMISSION Reference Symptom Probable Cause Solution Page Gears Clash When Synchronizer unit damaged Repair or replace 3-S38 Shifting Clutch does not release Adjust 2-S5 Differential Lock Can Differential lock shift fork damage Replace 3-S33 Not Be Set Differential lock shift fork mounting spring pin...
M108S, WSM TRANSMISSION 2. SERVICING SPECIFICATIONS Item Factory Specification Allowable Limit Shuttle Rod Length 65 mm – 2.6 in. Main Shift Rod 1 Length 489 mm – 19.3 in. Main Shift Rod 2 Length 120 mm – (Initial adjustment) 4.72 in.
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M108S, WSM TRANSMISSION Item Factory Specification Allowable Limit Piston Flatness – 0.15 mm 0.0059 in. Internal Snap Ring and Pressure Plate Clearance 1.5 to 2.0 mm 3.5 mm (4WD Clutch) 0.059 to 0.079 in. 0.138 in. Drive Plate (4WD Clutch) Thickness 1.7 to 1.8 mm...
M108S, WSM TRANSMISSION 3. TIGHTENING TORQUES Tightening torques of screws, bolts and nuts on the table below are especially specified. (For general use screws, bolts and nuts : Refer to “5. TIGHTENING TORQUES” at “G.GENERAL” section.) Item N·m kgf·m lbf·ft...
M108S, WSM TRANSMISSION 4. CHECKING AND ADJUSTING [1] SHUTTLE LEVER (1) Hydraulic Shuttle Model CAUTION • Park the machine on a firm, flat and level surface, set the parking brake and place the gear shift in neutral. • Stop the engine and remove the key before checking and adjusting.
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M108S, WSM TRANSMISSION Adjusting Shuttle Valve Neutral Position and Lever Guide Neutral Position (Continued) 7. Shift the free play “D” toward the forward direction and slowly lower the shuttle lever as shown in the figure. And visually inspect the clearance “X”.
M108S, WSM TRANSMISSION (2) Engine Start Condition Engine Start Condition IMPORTANT • Before starting the engine, make sure the gear shift lever at the neutral position. • Place the PTO lever to the OFF position. • Apply the parking brake.
M108S, WSM TRANSMISSION [2] MAIN GEAR SHIFT Checking Function of Main Gear Shift and Swing Shift (HI-LO) 1. Check the function of the main gear shift and swing shift (HI-LO). - Neutral position to 1st gear position. - Neutral position to 2nd gear position.
M108S, WSM TRANSMISSION [3] RANGE SHIFT LEVER Check Function of Range Shift 1. Check the function of the range gear shift. - Hi and Lo position. 2. If feeling abnormal shifting, check the length of range gear shift rod (2).
M108S, WSM TRANSMISSION [4] HYDRAULIC SHUTTLE OPERATING PRESSURE Checking of System Pressure 1. Remove the floor mat and inspection plate under the mat. 2. Remove the each plugs of F, R, M and set the adaptor D (1), threaded joint (4), cable (3), and pressure gauge (Code No.: 07916-52961) (2).
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M108S, WSM TRANSMISSION Checking Regulator Valve Setting Pressure 1. Remove the plug (4) and set the adaptor D, threaded joint, cable and pressure gauge. 2. Start the engine and set the engine at maximum speed. 3. Check the regulator valve setting pressure.
M108S, WSM TRANSMISSION [5] DUAL SPEED / 4WD OPERATING PRESSURE Checking of Operating Pressure 1. Starting the engine and warm up the transmission fluid, and then stop the engine. 2. Remove the each plugs of A, B, C, D and set the adaptor (PT 1/ 8) (use the oil pressure tester for diesel engine : Code No.
Transmission fluid 63.4 U.S.qts. 52.7 Imp.qts. IMPORTANT • Use only KUBOTA SUPER UDT fluid. Use of other oil may damage the transmission or hydraulic system. • Refer to “LUBRICANTS, FUEL AND COOLANT” at “G. GENERAL” section. • Do not mixed different brands fluid together.
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M108S, WSM TRANSMISSION Propeller Shaft 1. Slide the propeller shaft cover (3) after removing the screw (5). 2. Tap out the spring pins (2) and then slide the coupling (1) to the rear. (When reassembling) • Apply grease to the splines of the propeller shaft (6) and pinion shaft.
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M108S, WSM TRANSMISSION Fuel Tank and Auxiliary Step 1. Remove the auxiliary steps (1), (2). 2. Disconnect the 2P connector fuel tank unit (3). 3. Disconnect the fuel tank connector hose between left and right side fuel tanks. 4. Remove the fuel tank bands (4).
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M108S, WSM TRANSMISSION Gear Pump and Pump Base 1. Remove the suction pipes (1). 2. Remove the delivery pipes (2). 3. Remove the PTO pipe (3). 4. Remove the pump base with gear pumps. (When reassembling) • Replace the oil pipes with new ones and apply oil to them.
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M108S, WSM TRANSMISSION Dismounting Hydraulic Cylinder Assembly 1. Remove the hydraulic cylinder assembly mounting screws and nut. Support the hydraulic cylinder assembly (1) with nylon lift strap and hoist, and then remove it. 2. Dismounting the hydraulic cylinder assembly from transmission.
M108S, WSM TRANSMISSION [2] DISASSEMBLING SHUTTLE CASE Shuttle Case Assembly CAUTION • The shuttle case assembly is heavy, so that take care it when handling. 1. Remove the screws and nut. 2. Remove the shuttle case assembly (1) by using M8 x Pitch 1.25 screws into holes A and B.
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M108S, WSM TRANSMISSION Shuttle Clutch Assembly 1. Remove the internal snap ring (1). 2. Remove the pressure plate (2), drive plates (3), (4) and clutch discs (5). 3. Remove the bearing (12). 4. Press the thrust collar (13) lightly with hand press, using hydraulic clutch spring compressor (15) (refer to “8.
M108S, WSM TRANSMISSION [3] DISASSEMBLING SPEED CHANGE COVER Speed Change Cover 1. Remove the shuttle valve (1). 2. Remove the speed change cover (2). (When reassembling) • When reassembling the speed change cover (2) to clutch housing, set the 1-2 shift fork (4), 3-4 shift fork (5) and shifter in the transmission on neutral position, and Hi-Lo shift fork (3) and shifter in the transmission on Lo side.
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M108S, WSM TRANSMISSION Hi-Lo Shift Fork 1. Remove the Hi and Lo monitor switch (9). 2. Remove the internal snap ring (1) and seal cap (2). 3. Remove the spring pin (4). 4. Remove the fork rod (3) by using M6 x Pitch 1 screw into the thread (10).
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M108S, WSM TRANSMISSION Shift Fork and Fork Rod 1. Set the both shift fork on neutral position. 2. Remove the both safety switches (10) on 1-2 shift fork rod (8) and 3-4 shift fork rod (7). 3. Remove the spring pin (3), (4).
M108S, WSM TRANSMISSION [4] DISASSEMBLING CLUTCH HOUSING Bearing Support and Main Shaft 1. Remove the bearing retainers (1). 2. Remove the external snap ring (2). 3. Tap out the main shaft (6) to the rear. 4. Remove the bearing support (5) by M8 x Pitch 1.25 screws into holes (A), (B).
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M108S, WSM TRANSMISSION Counter Shaft 1. Tap out the counter shaft (1) to front through the hole of clutch hub (2). 2. Remove the external snap ring (3), then tap in the clutch hub (2) with bearing to the clutch housing.
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M108S, WSM TRANSMISSION Transmitting Shaft and Clutch Assembly 1. Install M6 x Pitch 1 mm screw on to the oil pipe (19) and pull out the oil pipes (19) by hand. 2. Remove the bearing support (front) mounting screws and remove the bearing support (8) with transmitting shaft (front) (12) by screwing M8 screws into holes (A).
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M108S, WSM TRANSMISSION Hydraulic Clutch (4WD) Assembly 1. Remove the internal snap ring (1). 2. Take out the pressure plate (2), clutch discs (3) and drive plates (4). 3. Remove the external snap ring (5) with the clutch compression tool.
M108S, WSM TRANSMISSION [5] DISASSEMBLING MID CASE Bearing Support and Dual Speed Clutch 1. Tap out the 27T gear shaft (2) and 25T gear (4) with bearing (3) together. 2. Remove the bearing (6) and external snap ring (5). 3. Remove the bearing support mounting screws.
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M108S, WSM TRANSMISSION Dual Speed Clutch Assembly 1. Remove the thrust collar (1) at LO clutch side. 2. Remove the internal snap ring (2). 3. Take out the pressure plate (3), clutch disc (4) and drive plate (5). 4. Press the spring retainer plate (6) lightly with clutch compression tool (8) (refer to “8.
M108S, WSM TRANSMISSION [6] DISASSEMBLING HI-LO SHIFT CASE (CREEP GEAR CASE) Hi-Lo Shift Case 1. Remove the HI-LO shift case mounting screws. 2. Remove the HI-LO shift case (1) by using M6 x Pitch 1 screws into holes A and B.
M108S, WSM TRANSMISSION [7] DISASSEMBLING PTO GEAR CASE Rear Cover Assembly 1. Remove the rear cover and PTO drive shaft as a unit. (When reassembling) 78 to 90 N·m Rear cover mounting Tightening torque 7.9 to 9.2 kgf·m screw 58 to 66 lbf·ft...
M108S, WSM TRANSMISSION [8] DISASSEMBLING DIFFERENTIAL GEAR Shift Fork and Shift Rod 1. Remove the HI-LO shift case mounting screws. 2. Remove the HI-LO shift case (4) by M6 x Pitch 1 screws in to the holes. 3. Remove the HI-LO shift fork (3) with fork rod (2) after removing the fork rod setting screws (6).
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M108S, WSM TRANSMISSION PTO Clutch Assembly 1. Remove the bearing retainer (1). 2. Tap out the coupling (2) with bearing to the rear. 3. Remove the internal snap ring (3). 4. Remove the external snap ring (4). 5. Tap out the PTO clutch shaft (5) to the front and remove the PTO clutch assembly (6).
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M108S, WSM TRANSMISSION Differential Gear Assembly 1. Remove the differential support (1), (5), noting the number of left and right shims (2), (4). 2. Take out the differential gear assembly (3) from transmission case. (When reassembling) • Be sure to adjust the turning torque of spiral bevel pinion shaft and differential assembly combined.
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M108S, WSM TRANSMISSION Taper Roller Bearing 1. Place the differential cover (1) on the vise. 2. Tap out the taper roller bearing (2) from the inside of the differential cap, taking care not to damage the outer race and separator.
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M108S, WSM TRANSMISSION Spiral Bevel Pinion Shaft 1. Remove the stake of the staking nut (1). 2. Set the pinion locking tool (2) (Code No. 07916-52311). 3. Remove the staking nut (1). 4. Tap out the bevel pinion shaft (3) to the rear.
M108S, WSM TRANSMISSION 6. SERVICING [1] BEARING, SHIFT FORK AND SYNCHRONIZER Checking Bearing 1. Hold the inner race, and push and pull the outer race in all directions to check for wear and roughness. 2. Apply transmission fluid to the bearing, and hold the inner race.
M108S, WSM TRANSMISSION [2] SHUTTLE CLUTCH Clearance between Internal Snap Ring and Pressure Plate 1. Measure the clearance between internal snap ring and pressure plate with a feeler gauge while applying the specified force. Specified force : 177 to 294 N (18.0 to 30.0 kgf, 39.7 to 66.1 lbf).
M108S, WSM TRANSMISSION [3] THRUST CLEARANCE ON SHAFT Checking side clearance on Main Shaft Gear 1. Measure the side clearance between thrust bearing and bearing washer. 2. If the measurement is not within the factory specifications, adjust the clearance with shim on the front end of main shaft.
M108S, WSM TRANSMISSION [4] DUAL SPEED CLUTCH Clearance between Internal Snap Ring and Pressure Plate 1. Measure the clearance between internal snap ring and pressure plate with a feeler gauge while applying the specified force. Specified force: 177 to 294 N (18.0 to 30.0 kgf, 39.7 to 66.1 lbf).
M108S, WSM TRANSMISSION [5] 4WD CLUTCH Clearance between Internal Snap Ring and Pressure Plate 4WD Clutch 1.5 to 2.0 mm Factory spec. Clearance between 0.059 to 0.079 in. internal snap ring and 3.5 mm pressure plate Allowable limit 0.138 in.
M108S, WSM TRANSMISSION [6] DIFFERENTIAL GEAR IMPORTANT • When reassembling spiral bevel pinion shaft and differential assembly, be sure to adjust the following. • Turning torque of spiral bevel pinion shaft only. • Turning torque of spiral bevel pinion shaft and differential assembly combined.
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M108S, WSM TRANSMISSION Turning torque of Spiral Bevel Pinion Shaft and Differential Assembly Combined 1. Reassemble the differential assembly with left shims (2) and right shims (1) same as before assembling. 2. Check that there is a backlash. If there is no backlash, remove a right shim (1) and add a left shim (2).
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M108S, WSM TRANSMISSION Backlash and Tooth Contact between Spiral Bevel Gear and Spiral Bevel Pinion Shaft 1. Set the dial indicator (lever type) with its finger on the tooth surface. 2. Measure the backlash by fixing the spiral bevel pinion shaft (1) and moving the spiral bevel gear (2) by hand.
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M108S, WSM TRANSMISSION • Proper Contact More than 35 % red lead contact area on the gear tooth surface. The center of tooth contact at 1/3 of the entire width from the small end. (A) Proper Contact W1049310 • Shallow or Heel Contact Replace the adjusting collar (5) with thicker one to move the spiral bevel pinion shaft backward.
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M108S, WSM TRANSMISSION Clearance between Differential Case Bore (Differential Case Cover Bore) and Differential Side Gear Boss 1. Measure the bore I.D. of the differential case and differential case cover. 2. Measure the differential side gear boss O.D. and calculate the clearance.
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M108S, WSM TRANSMISSION Backlash between Differential Pinion and Differential Side Gear 1. Set a dial indicator (lever type) on the tooth of the differential pinion. 2. Hold the differential side gear and move the differential pinion to measure the backlash.
M108S, WSM REAR AXLE 1. TROUBLESHOOTING Reference Symptom Probable Cause Solution Page Excessive or Improper backlash between brake shaft’s 12T Replace – Unusual Noise at All gear and planetary gear Time Improper backlash between planetary gear and Replace 4-S7, 9...
M108S, WSM REAR AXLE 2. SERVICING SPECIFICATIONS Item Factory Specification Allowable Limit Internal Gear to Planetary Gear Backlash 0.10 to 0.20 mm 0.50 mm 0.0040 to 0.0078 in. 0.020 in. Planetary Gear Thrust Collar Thickness 1.55 to 1.65 mm 1.2 mm 0.0611 to 0.0649 in.
M108S, WSM REAR AXLE 3. TIGHTENING TORQUES Tightening torques of screws, bolts and nuts on the table below are especially specified. (For general use screws, bolts and nuts : Refer to “5. TIGHTENING TORQUES” at “G.GENERAL” section.) Item N·m kgf·m lbf·ft...
Transmission fluid 63.4 U.S.qts. 52.7 Imp.qts. IMPORTANT • Use only KUBOTA SUPER UDT fluid. Use of other oil may damage the transmission or hydraulic system. • Refer to “4. LUBRICANTS, FUEL AND COOLANT” at “G. GENERAL” section. • Do not mixed different brands fluid together.
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M108S, WSM REAR AXLE Rear Wheel and 3-Points Hitch 1. Set the front axle rocking restrictor (refer to “8. SPECIAL TOOLS” at “G. GENERAL” section) (1) to the front axle. 2. Place the disassembling stand under the transmission case. 3. Remove the rear wheel (2).
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M108S, WSM REAR AXLE Cabin Mount Bracket Rear 1. Remove the cabin mounting screw and nut (1). 2. Hoist the cabin. 3. Remove the stabilizer bracket (2). 4. Raise the cabin until the rear bracket becomes free to move. 5. Remove the rear bracket (3).
M108S, WSM REAR AXLE (2) Disassembling Rear Axle Case Planetary Gear Support 1. Remove the planetary gear support mounting UBS screw (1). 2. Remove the planetary gear support (2). (When reassembling) 90.3 to 103 N·m Planetary gear support Tightening torque 9.20 to 10.6 kgf·m...
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M108S, WSM REAR AXLE Rear Axle Nut 1. Fix the rear axle on the repair table or set to the rear wheel. 2. Remove the stake on the rear axle nut. 3. Remove the rear axle nut with a rear axle nut wrench 98 (Code No.
M108S, WSM REAR AXLE [2] SERVICING Backlash between Internal Gear and Planetary Gear 1. Set a dial indicator (lever type) on the tooth of the planetary gear. 2. Hold the planetary gear support and move only the planetary gear to measure the backlash.
M108S, WSM BRAKES 1. TRAVELLING BRAKE The travelling brake is a hydraulic wet disc type, which consists of the master cylinder (10), equalizer (12), brake pipe (8), brake oil reservoir (11) and others. This type provides high and stable braking effect and requires almost no adjustment.
M108S, WSM BRAKES 2. HYDRAULIC TRAILER BRAKE VALVE [1] STRUCTURE Main Elements • Flow control valve (10) with throttle (9) and restrictor (11) : for controlling the delivery flow Qp and for regulating the fluid flow for the trailer brake.
M108S, WSM BRAKES [2] OPERATION Tractor Brake Released The tractor service brake line X is pressureless. The brake line B is relieved to the reservoir through the control spool (2) and port R. The delivery flow Qp of the pump flows from port P past flow control valve (10), the flow Qp - Qx continues through port N to the tractor hydraulics.
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M108S, WSM BRAKES Partial Braking of Trailer Brake - Initiation Piston (7) of control head (6) is pressurized through control line X from the tractor service brake. Control spool (2) is thus shifted to the left and separates from the reservoir first brake line B and then bore (8).
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M108S, WSM BRAKES Partial Braking of Trailer Brake The trailer braking pressure Pb (acting on surface (1) of control spool (2)) is in equilibrium with the tractor braking pressure Px (acting on piston (7)). The brake line B remains separated from the reservoir and the oil in the trailer brake is thus enclosed.
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M108S, WSM BRAKES Maximum Braking of Trailer Brake - Braking Pressure Limited Flow control valve (10) and control spool (2) have the same spool positions (a and d) as in the case of partial braking. The fluid flows Qp and Qx pass as with partial braking.
M108S, WSM BRAKES 2. SERVICING SPECIFICATIONS TRAVELING BRAKE Item Factory Specification Allowable Limit Brake Pedal Play 7.0 to 14 mm – 0.28 to 0.55 in. Right and Left Less than 100 mm – (Stroke) 3.94 in. Difference 0 to 5.0 mm –...
M108S, WSM BRAKES 3. TIGHTENING TORQUES Tightening torques of screws, bolts and nuts on the table below are especially specified. (For general use screws, bolts and nuts : Refer to “5. TIGHTENING TORQUES” at “G.GENERAL” section.) Item N·m kgf·m lbf·ft...
M108S, WSM BRAKES 4. CHECKING, DISASSEMBLING AND SERVICING [1] CHECKING AND ADJUSTING Adjusting Brake Pedal 1) Brake Pedal Free Travel CAUTION • When checking, parking the tractor on flat ground, and stop the engine. 1. Measure the free travel by depressing the brake pedals.
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M108S, WSM BRAKES 3) Equalizer Working Level 1. Gently step on both the right and left pedals at once with your both feet. Step on the right pedal all the way (the left pedal rises). Measure the level difference between the two pedals.
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M108S, WSM BRAKES Brake Test 1. Remove the bleeder from brake case and set the hydraulic brake adaptor (Code No. 07916-52970) (1), joint (Code No. 07916- 50401) (2), cable (Code No. 07916-50331) (3) and pressure gauge (Code No. 07916-52961) (4).
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M108S, WSM BRAKES Bleeding Brake System NOTE • While bleeding, make sure to keep enough brake oil in the brake oil reservoir. 1. Disconnect the brake pipes (1) from the master cylinder. 2. Move the brake pedal up and down by hand. At this time, when raising the pedal, close the master cylinder outlet by a finger, and when lowering, release the finger.
M108S, WSM BRAKES [2] DISASSEMBLING AND ASSEMBLING (1) Removing Brake Pedal Brake Pedal 1. Remove the meter panel. 2. Remove the bonnet rear. 3. Remove the brake pedal return spring and clevis pin from the turnbuckle of master cylinder. 4. Remove the circlip (4) and spring pin (5) and draw out the brake pedal shaft (1), then remove the left and right brake pedal (2), (3).
M108S, WSM BRAKES (2) Removing Master Cylinder and Equalizer Removing Master Cylinder and Equalizer Precaution of Disassembling and Assembling for Hydraulic Brake • Wash all parts with clean brake oil (refer to “4. LUBRICANTS, FUEL AND COOLANT” at “G. GENERAL” section).
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M108S, WSM BRAKES Master Cylinder 1. Drain the brake oil from the master cylinder. 2. Secure the master cylinder in a vise. Remove the push rod (3) and boot (4) as a unit from the master cylinder. 3. Remove the internal snap ring (5), and pull out the piston (6), return spring (7) and outlet valve (8).
Transmission fluid 63.4 U.S.qts. 52.7 Imp.qts. IMPORTANT • Use only KUBOTA SUPER UDT fluid. Use of other oil may damage the transmission or hydraulic system. • Refer to “4. LUBRICANTS, FUEL AND COOLANT” at “G. GENERAL” section. • Do not mixed different brands fluid together.
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M108S, WSM BRAKES Rear Wheel and 3-Points Hitch 1. Set the front axle rocking restrictor (refer to “8. SPECIAL TOOLS” at “G. GENERAL” section) (1) to the front axle. 2. Place the disassembling stand under the transmission case. 3. Remove the rear wheel (2).
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M108S, WSM BRAKES Cabin Mount Bracket Rear 1. Remove the cabin mounting screw and nut (1). 2. Hoist the cabin. 3. Remove the stabilizer bracket (2). 4. Raise the cabin until the rear bracket becomes free to move. 5. Remove the rear bracket (3).
M108S, WSM BRAKES Parking Brake Pad 1. Remove the E snap ring (1), and put out the parking brake camshaft (2) and parking brake cam (3). 2. Straighten the lock plate (4) and loosen the nut (5). 3. Remove the parking brake pads.
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M108S, WSM BRAKES Brake Disc Wear 1. Measure the brake disc thickness with a vernier caliper. 2. If the measurement is less than the allowable limit, replace it. 4.15 to 4.35 mm Factory spec. 0.164 to 0.171 in. Brake disc wear 3.3 mm...
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M108S, WSM FRONT AXLE 1. STRUCTURE The front axle supports the front of tractor and facilitates steering. There are two kinds of front axles. The two-wheel drive axle has free-running front wheels and the four-wheel drive axle has powered front wheels.
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SERVICING CONTENTS 1. TROUBLESHOOTING ..................6-S1 2. SERVICING SPECIFICATIONS ..............6-S2 3. TIGHTENING TORQUES ................6-S3 4. CHECKING, DISASSEMBLING AND SERVICING........6-S4 [1] CHECKING AND ADJUSTING ...............6-S4 [2] DISASSEMBLING AND ASSEMBLING..........6-S6 (1) Separating Front Axle [4WD Type] .............6-S6 (2) Disassembling Front Axle [4WD Type] ..........6-S10 [3] SERVICING ....................6-S17 (1) 4WD Type ..................6-S17 KiSC issued 06, 2007 A...
M108S, WSM FRONT AXLE 1. TROUBLESHOOTING Reference Symptom Probable Cause Solution Page Front Wheels Tire pressure uneven Adjust G-69 Wander to Right or Improper toe-in adjustment (improper alignment) Adjust 6-S4 Left Clearance between front axle case boss and Replace 6-S24...
M108S, WSM FRONT AXLE 2. SERVICING SPECIFICATIONS [4WD TYPE] Item Factory Specification Allowable Limit Front Wheel Alignment Toe-in 2.0 to 8.0 mm – 0.079 to 0.31 in. Front Wheel Axle Sway 5.0 mm – 0.20 in. Steering Angle 0.84 to 0.87 rad –...
M108S, WSM FRONT AXLE 3. TIGHTENING TORQUES Tightening torques of screws, bolts and nuts on the table below are especially specified. (For general use screws, bolts and nuts : Refer to “5. TIGHTENING TORQUES” at “G.GENERAL” section.) [4WD] Item N·m kgf·m...
M108S, WSM FRONT AXLE 4. CHECKING, DISASSEMBLING AND SERVICING [1] CHECKING AND ADJUSTING Adjusting Toe-in 1. Park tractor on a flat place. 2. Turn steering wheel so that front wheels are in the straight ahead position. 3. Lower the implement, lock the park brake and stop the engine.
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M108S, WSM FRONT AXLE Adjusting Front Axle Pivot 1. Jack up the tractor body, then loosen the lock nut (2). 2. Measure the adjusting screw tightening torque. 3. If tightening torque is not within the factory specifications, adjust the adjusting screw (1).
M108S, WSM FRONT AXLE Front Wheel Steering Angle 1. Inflate the tires to the specified pressure. 2. Adjust turning angle with the stopper bolts table below. 3. The right side is similarly adjusted. IMPORTANT • Always check if tires contact with tractor or loader frame assemblies.
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M108S, WSM FRONT AXLE Draining Front Axle Gear Case Oil 1. To drain the used oil, remove the right and left drain plugs (2) and filling plugs (1) at the front axle gear case and drain the oil completely into the oil pan.
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M108S, WSM FRONT AXLE Front Wheel and Power Steering Hoses 1. Check the front axle and engine are securely mounted on the disassembly stand. 2. Loosen the front wheel mounting nuts. 3. Lift the front axle and remove the front wheels.
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M108S, WSM FRONT AXLE Front Axle 1. Place a disassembling stand under the front axle bracket and support it with jack. 2. Hoist and hold the front axle with nylon slings. 3. Loosen the lock nut (1) and remove the spring (2) from differential lock lever (3).
M108S, WSM FRONT AXLE (2) Disassembling Front Axle [4WD Type] Tie-rod 1. Pull out the cotter pin and remove the tie-rod end slotted nuts. 2. Remove the tie-rod with a tie-rod end lifter (Code No. 07909- 39051). (When reassembling) • Replace cotter pin with a new one.
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M108S, WSM FRONT AXLE Bevel Gear Case 1. Separate the bevel gear case (3) from front wheel case (4). 2. Remove the front wheel case support (1). 3. Loosen the bearing retainer (2) mounting screws. 4. Remove the bearing retainer (2) by screwing M8 screw into holes A and B.
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M108S, WSM FRONT AXLE Front Wheel Case 1. Remove the internal snap ring (13). 2. Remove the cap (12) which is installed in the bottom of front wheel case. 3. Remove the internal snap ring (11) and take out the adjusting shims (10).
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M108S, WSM FRONT AXLE Planetary Gear 1. Remove the external snap ring (1). 2. Remove the planetary gear support assembly. 3. Tap the spring pin (6) into the planetary gear shaft (5). 4. Draw out the planetary gear shaft (5), and remove the planetary gear (3).
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M108S, WSM FRONT AXLE Bevel Gear and Differential Yoke Shaft 1. Remove the bevel gear (5), bearing (4) and differential yoke shaft (3) as a unit from the differential case (1). 2. Remove the external snap ring (6) and remove the bevel gear (5).
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M108S, WSM FRONT AXLE Differential Assembly 1. Remove the plug (2), and tap out the spring pin (3). 2. Draw out the differential lock lever shaft (1). 3. Remove the differential lock lever (4). 4. Remove the bearing support 1 (7) and shim (8) and differential lock clutch 2 (9).
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M108S, WSM FRONT AXLE Spiral Bevel Gear 1. Remove the spiral bevel gear UBS screws. 2. Tap out the spiral bevel gear (2) from the differential gear case. (When reassembling) • Apply lock tight (Three Bond 1324B or equivalent) to the spiral bevel gear UBS screws.
M108S, WSM FRONT AXLE [3] SERVICING (1) 4WD Type Backlash and Tooth Contact between Bevel Pinion Shaft and Bevel Gear 1. Set a dial indicator (lever type) with its finger on the tooth surface. 2. Measure the backlash by fixing the bevel pinion shaft (5) and moving the bevel gear (3) by hand.
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M108S, WSM FRONT AXLE Clearance between Differential Case and Differential Side Gear 1. Measure the differential side gear boss O.D.. 2. Measure the differential case bore I.D., and calculate the clearance. 3. If the clearance exceeds the allowable limit, replace it.
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M108S, WSM FRONT AXLE Front Bracket and Rear Bracket Bushing 1. Visually inspect the DX bushing for signs of wear or damage. (The DX bushing tends to show concentrated wear.) 2. If the DX bushing is worn beyond the alloy portion (A), replace it.
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M108S, WSM FRONT AXLE Bevel Gear Case and Front Wheel Case Bushing 1. Visually inspect the DX bushing for signs of wear or damage. (The DX bushing tends to show concentrated wear.) 2. If the DX bushing is worn beyond the alloy portion (A), replace it.
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M108S, WSM FRONT AXLE Backlash between Internal Gear and Planetary Gear 1. Set a dial indicator (lever type) on the tooth of the planetary gear. 2. Hold the planetary gear support and move only the planetary gear. 3. If the measurement exceeds the allowable limit, check the planetary gear and planetary shaft.
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M108S, WSM FRONT AXLE Backlash of Bevel Gear in Front Wheel Case 1. Set a dial indicator (lever type) on the shaft (Kingpin). 2. Move the shaft (Kingpin) by hand and measure the circumferential play of the shaft. 3. Calculate the backlash from the ratio of the shaft diameter to the gear diameter.
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M108S, WSM STEERING 1. STRUCTURE [1] STEERING MECHANISM This model is provided with a full hydrostatic power steering. Generally power steerings are divided into 4 types: booster type, integral type, semi-integral type and full hydrostatic type. In the full hydrostatic power steering, the steering controller is connected to the steering cylinder with only the hydraulic pipe.
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SERVICING CONTENTS 1. TROUBLESHOOTING ..................7-S1 2. SERVICING SPECIFICATIONS ..............7-S2 3. TIGHTENING TORQUES ................7-S3 4. CHECKING, DISASSEMBLING AND SERVICING........7-S4 [1] CHECKING AND ADJUSTING ...............7-S4 (1) Hydraulic Pump for Power Steering............7-S4 (2) Power Steering Relief Valve ...............7-S5 [2] DISASSEMBLING AND ASSEMBLING..........7-S6 (1) Hydraulic Pump...................7-S6 (2) Removing Steering Controller .............7-S8 (3) Removing Steering Cylinder ...............7-S9 (4) Steering Controller Assembly ............7-S10...
M108S, WSM STEERING 3. TIGHTENING TORQUES Tightening torques of screws, bolts and nuts on the table below are especially specified. (For general use screws, bolts and nuts : Refer to “5. TIGHTENING TORQUES” at “G.GENERAL” section.) Item N·m kgf·m lbf·ft...
[1] CHECKING AND ADJUSTING (1) Hydraulic Pump for Power Steering Hydraulic Flow Test IMPORTANT • When using flowmeter other than KUBOTA specified flowmeter, be sure to use the instructions with the flowmeter. • Do not close the flowmeter loading valve completely, before testing, because it has no relief valve.
M108S, WSM STEERING [2] DISASSEMBLING AND ASSEMBLING (1) Hydraulic Pump Removing Hydraulic Pump 1. Remove the floor mat (1) and inspection plate under the mat. 2. Remove the seat (2) and floor cover (3). 3. Disconnect the delivery pipe 1 (4) and delivery pipe (5).
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M108S, WSM STEERING Disassembling Hydraulic Pump 1. Put parting marks (A), (B) on the front cover (3), body (7) and housing rear cover (9). 2. Remove the housing rear cover (9) and body (7). 3. Remove the side plate (5).
M108S, WSM STEERING (3) Removing Steering Cylinder Tie-rod 1. Pull out the cotter pin and remove the tie-rod end slotted nuts. 2. Remove the tie-rod with a tie-rod end lifter (Code No. 07909- 39051). (When reassembling) • Replace cotter pin with a new one.
M108S, WSM STEERING (4) Steering Controller Assembly Relief Valve Assembly 1. Remove the adjust plug (3) and draw out the spring (2) and poppet (1). (When reassembling) • Take care not to damage the O-ring. IMPORTANT • After disassembling and assembling the relief valve, be sure to adjust the relief valve setting pressure.
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M108S, WSM STEERING Grand Seal, Needle Bearing, Sleeve and Spool 1. Remove the retaining ring (1) with a screw driver. 2. Hold the control valve unit vertically and spool and sleeve align the cross pin parallels to flat side of housing (flow priority valve mounting side), the cross pin is visible through open end of spool.
M108S, WSM STEERING Sleeve and Spool 1. Draw out the dowel pin (1). 2. Draw out the spool (3) from the sleeve (2). 3. Push out the centering spring (4). IMPORTANT • As the clearance between the sleeve (2) and spool (3) is very narrow, draw out the spool by turning it slowly with due care.
M108S, WSM STEERING [3] SERVICING (1) Hydraulic Pump Housing Bore 1. Measure the housing I.D. where the interior surface is not scratched, and measure the housing I.D. where the interior surface is scratched. 2. If the values obtained in the two determinations differ by more than the allowable limit, replace the hydraulic pump as a unit.
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HYDRAULIC SYSTEM KiSC issued 06, 2007 A...
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MECHANISM CONTENTS 1. STRUCTURE ....................8-M1 2. HYDRUALIC CIRCUIT .................. 8-M3 [1] HYDRAULIC CIRCUIT................8-M4 [2] CONTROL VALVE .................. 8-M5 [3] POSITION CONTROL ................8-M7 KiSC issued 06, 2007 A...
(10) Oil Cooler (13) Oil Filter Cartridge The hydraulic system of M108S tractor is composed of three point hitch, remote hydraulic control for implements, power steering, PTO clutch, shuttle clutch, swing shift and dual speed shown above. This system has following functions.
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M108S, WSM HYDRAULIC SYSTEM 6. To operate swing shift HI-LO. The swing shift (HI-LO) is controlled by the combination of solenoid valve and hydraulic flow. Two ways of power train are available low speed range and high speed range of travelling speed.
M108S, WSM HYDRAULIC SYSTEM [2] CONTROL VALVE Neutral Pressurized oil from the P port, pushes and opens unload poppet 1 (4) and returns to tank from T1 port. The oil in the chamber A behind the unload poppet 1 (4) returns to the tank through the E of spool (3) and control valve body.
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M108S, WSM HYDRAULIC SYSTEM Lifting Neutral (Acting shockless mechanism) In returning from Lifting to Neutral, the spool (3) is pushed back to the arrow-mark direction. When the Neutral position comes near, the groove part D of the spool (3) makes the pressure difference at the P port and C port.
M108S, WSM HYDRAULIC SYSTEM [3] POSITION CONTROL Position control is a system to raise and lower the implement proportionally to the movement of the position control lever. With this system, the implement can be raised or lowered to any position desired by changing the position of the control lever and fine adjustment is also easy.
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SERVICING CONTENTS 1. TROUBLESHOOTING ..................8-S1 2. SERVICING SPECIFICATIONS ..............8-S2 3. TIGHTENING TORQUES ................8-S4 4. CHECKING, DISASSEMBLING AND SERVICING........8-S5 [1] CHECKING AND ADJUSTING ...............8-S5 (1) Hydraulic Pump for Three-Point Hitch ..........8-S5 (2) Three-Point Hitch System (Relief Valve and Safety Valve) Operating System ....................8-S6 (3) Three-Point Hitch Control Linkage .............8-S7 (4) Auxiliary Control Valve Wire .............8-S10...
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M108S, WSM HYDRAULIC SYSTEM 1. TROUBLESHOOTING Reference Symptom Probable Cause Solution Page Implement Does Not Control linkage improperly assembled or Repair or replace 8-S7 Rise (Not Noise) damaged Control valve malfunctioning (unload valve, Repair or replace 8-S14 spool, check valve, poppet valve)
M108S, WSM HYDRAULIC SYSTEM 2. SERVICING SPECIFICATIONS HYDRAULIC PUMP FOR THREE-POINT HYDRAULIC SYSTEM Item Factory Specification Allowable Limit Hydraulic Pump Delivery Above 53.2 L/min. 66.6 L/min. 14.1 U.S.gals/min. 17.6 U.S.gals/min. 11.7 Imp.gals/min. 14.6 Imp.gals/min. Housing Bore Depth of Scratch –...
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M108S, WSM HYDRAULIC SYSTEM HYDRAULIC CYLINDER Item Factory Specification Allowable Limit Cylinder Bore I.D. 100.036 to 100.071 mm 100.15 mm 3.93843 to 3.93980 in. 3.9429 in. Hydraulic Arm Shaft to Bushing Clearance (Right) 0.140 to 0.250 mm 0.50 mm 0.00552 to 0.00984 in.
M108S, WSM HYDRAULIC SYSTEM 3. TIGHTENING TORQUES Tightening torques of screws, bolts and nuts on the table below are especially specified. (For general use screws, bolts and nuts : Refer to “5. TIGHTENING TORQUES” at “G.GENERAL” section.) Item N·m kgf·m lbf·ft...
[1] CHECKING AND ADJUSTING (1) Hydraulic Pump for Three-Point Hitch Hydraulic Flow Test IMPORTANT • When using flowmeter other than KUBOTA specified flowmeter, be sure to use the instructions with the flowmeter. • Do not close the flowmeter loading valve completely, before testing, because it has no relief valve.
M108S, WSM HYDRAULIC SYSTEM (2) Three-Point Hitch System (Relief Valve and Safety Valve) Operating System Relief Valve Setting Pressure Test Using Pressure Tester (Coupler) 1. Set the relief valve set pressure adaptor G (Code No. 07916- 52751) to the half male of the quick coupler and then set a pressure gauge (Code No.
M108S, WSM HYDRAULIC SYSTEM (3) Three-Point Hitch Control Linkage Adjusting the Position Rod and Draft Rod 1. Be sure to adjust the position rod length A and draft rod length B. Position rod length A 369 mm Factory spec. and draft rod length B 14.5 in.
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M108S, WSM HYDRAULIC SYSTEM Adjusting Position Control Lever 1. Attach a weight of approx. 490 N (50 kgf, 110 lbf) to the end of the lower links. 2. Start the engine and set the speed at 1000 min (rpm). 3. Move the draft control lever (2) all the way down and shift the position control lever (1) downward by approx.
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M108S, WSM HYDRAULIC SYSTEM Adjusting Draft Control Rod 1. Attach a weight of approx. 490 N (50 kgf, 110 lbf) to the end of the lower links. 2. Start the engine and set the speed at 1000 min (rpm). 3. Move the position control lever and draft control lever (1) all the way down.
M108S, WSM HYDRAULIC SYSTEM Adjusting Top Link Bracket 1. Measure the clearance (A) between the stopper (3) and top link bracket (1). If the clearance is not within the factory specifications, adjust with the shims (4) between the stopper (3) and top link bracket (1).
M108S, WSM HYDRAULIC SYSTEM [2] DISASSEMBLING AND ASSEMBLING (1) Hydraulic Pump Removing Hydraulic Pump 1. Remove the floor mat (1) and inspection plate under the mat. 2. Remove the seat (2) and floor cover (3). 3. Disconnect the delivery pipe 1 (4) and delivery pipe (5).
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M108S, WSM HYDRAULIC SYSTEM Disassembling Hydraulic Pump 1. Put parting marks (A), (B) on the front cover (3), body (7) and housing rear cover (9). 2. Remove the housing rear cover (9) and body (7). 3. Remove the side plate (5).
M108S, WSM HYDRAULIC SYSTEM (2) Relief Valve for Three-Point Hitch Relief Valve 1. Remove the lock nut (9). 2. Remove the adjuster (8), and draw out the spring (7) and pilot valve (6). 3. Remove the valve seat (1), and draw out the valve seat (4), the spring (3) and the main valve (2).
M108S, WSM HYDRAULIC SYSTEM (4) Separating Three-Point Hitch Cylinder Assembly Preparation 1. Remove the seat and floor seat cover. 2. Remove the delivery pipe (1). 3. Disconnect the auxiliary control wire (3) and position and draft control rod (2). 4. Disconnect the lowering speed control rod (5).
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M108S, WSM HYDRAULIC SYSTEM Plug and Unload Valve 1. Secure the control valve with a vise. 2. Remove the seat plug 1 (1) for unload poppet 1 (3). 3. Draw out the spring (2) for unload poppet 1 (3). 4. Remove the seat plug 2 (4) for unload poppet 2 (6).
M108S, WSM HYDRAULIC SYSTEM (6) Control Valve Linkage Position and Draft Linkage 1. Remove the clevis pin (2). 2. Remove the circlips (4), (5), (6), (7). 3. Remove the stopper and draw out the rod (3). 4. Remove the stopper and draw out the rod (8). To remove the O- ring (22) and (23) order by c →...
M108S, WSM HYDRAULIC SYSTEM (7) Cylinder Assembly Lift Arm and Hydraulic Arm Shaft 1. Remove the wire and unscrew the setting screw (3). 2. Remove the screw (5) and lift arm L.H. (1). 3. Draw out the hydraulic arm shaft (2) and lift arm R.H. (4) as a unit.
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M108S, WSM HYDRAULIC SYSTEM Hydraulic Cylinder Cover and Hydraulic Piston 1. Remove the hydraulic cylinder cover (1). 2. Push out the hydraulic piston (5) from the hydraulic cylinder. (When reassembling) • Install the hydraulic piston, noting O-ring (6) and backup ring (7).
M108S, WSM HYDRAULIC SYSTEM [3] SERVICING (1) Hydraulic Pump Housing Bore 1. Measure the housing I.D. where the interior surface is not scratched, and measure the housing I.D. where the interior surface is scratched. 2. If the values obtained in the two determinations differ by more than the allowable limit, replace the hydraulic pump as a unit.
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M108S, WSM HYDRAULIC SYSTEM Clearance between Hydraulic Arm Shaft and Bushing 1. Measure the hydraulic arm shaft O.D. with an outside micrometer. 2. Measure the bushing I.D. with a cylinder gauge, and calculate the clearance. 3. If the clearance exceeds the allowable limit, replace the bushing.
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ELECTRICAL SYSTEM KiSC issued 06, 2007 A...
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MECHANISM CONTENTS 1. WIRING DIAGRAM ..................9-M1 [1] MAIN HARNESS..................9-M1 [2] ENGINE HARNESS ................9-M2 [3] CRS HARNESS ..................9-M3 [4] BODY HARNESS AND BONNET HARNESS........9-M4 [5] CABIN HARNESS................... 9-M5 2. ELECTRICAL CIRCUIT ................9-M6 [1] FUSE, STARTING SYSTEM AND CHARGING SYSTEM....9-M6 [2] METER SYSTEM..................
M108S, WSM ELECTRICAL SYSTEM [2] ENGINE HARNESS To Main Harness Diode (Compressor) 0.85 B 0.85 B 0.85 Y/L Earth Rear 2.00 B Compressor 0.50 Y/L Magnetic Clutch 0.50 B Earth Front 2.00 B Engine Oil Pressure 0.50 W Switch 0.50 W/R Engine Coolant 0.50 B/W...
M108S, WSM ELECTRICAL SYSTEM [4] BODY HARNESS AND BONNET HARNESS To Body Harness 14 13 12 11 10 9 7 6 5 4 3 2 0.85 W/R Front Side Work Light L.H. 0.85 B 1.25 BR 1.25 OR Head Light L.H.
M108S, WSM ELECTRICAL SYSTEM [5] CABIN HARNESS Rear Front Rear Wiper Front Wiper Work Light A/C Control Panel Blower Switch Dome Light Beacon Switch Work Light Mode Select Switch Switch Switch Switch Servomotor INT E WV+1 0.50 G/Y 0.5 Y 0.50 L/G...
M108S, WSM ELECTRICAL SYSTEM [5] LIGHTING SYSTEM Air Con/Position Flasher/Light Key IG1/IG Steering Assembly Horn Switch 0.85L/W FREE 0.85R/G PUSH 0.85G To Meter Panel 0.85BR 0.85BR 0.5BR Hazard Switch (Hi Beem) 14V1.4W 0.85OR Combination Light Switch FREE LOCK 0.85R/G To Radio (Back Up)
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M108S, WSM ELECTRICAL SYSTEM [6] WORK LIGHT, RADIO AND ACCESSORY Air Con/Position Flasher/Light Key ACC Key IG2 0.5Y/G To Compressor Relay 0.5Y/B To Compressor Relay 0.5Y/B 0.5Y/B 0.5Y/B To Blower Relay 0.5Y/B To Auxiliary Power Relay Work Light Relay 0.5Y/B...
M108S, WSM ELECTRICAL SYSTEM [7] WIPER SYSTEM Key IG2 0.85L 0.85L 0.85L Front Wiper Motor Relay 0.85L Front Wiper Motor 0.47 F Front Wiper Switch Rear Wiper Motor 0.85L/Y WV WM 3.0 H WASH 0.85LG/W -EC :Option 0.85LG/B WASH Washer Motor 0.85L...
M108S, WSM ELECTRICAL SYSTEM [8] AIR CONDITIONER 0.5Y/G To Front Side Work Light Relay Air Con/Def 0.5Y/G 0.5Y/B 0.5Y/B Key IG2 0.5Y/B 0.5Y/B To Auxiliary Power Relay 0.5Y/B To Work Light Relay Servomotor Mode Servomotor Temperature Control Blower Relay Compressor Relay Thermostat 0.5W...
M108S, WSM ELECTRICAL SYSTEM [9] COLOR OF WIRING B ... Black Br/Y ..Brown / Yellow R/W .... Red / White G ..Green Br/R ..Brown / Red R/Y ..... Red / Yellow L ... Blue G/B ..Green / Black W/B ....
M108S, WSM ELECTRICAL SYSTEM 3. EASY CHECKER [1] INDICATION ITEMS The operator must check the conditions of the tractor before and during operations. To facilitate checking, the Easy-Checker (TM) lamps on the panel board is provided. Easy Checker (TM) If the warning lamps in the Easy Checker (TM) come on during operation, immediately stop the engine, and find the cause as shown below.
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M108S, WSM ELECTRICAL SYSTEM Parking brake / Brake oil indicator 1. The warning lamp (4) in the Easy Checker (TM) comes on if the parking brake is applied. If the lamp is on during operation, release the parking brake lever immediately.
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SERVICING CONTENTS 1. TROUBLESHOOTING ..................9-S1 2. SERVICING SPECIFICATIONS ..............9-S6 3. TIGHTENING TORQUES ................9-S7 4. CHECKING AND ADJUSTING ..............9-S8 [1] BATTERY AND FUSE ................9-S8 (1) Battery....................9-S8 (2) Checking Fuse ..................9-S11 [2] MAIN SWITCH ..................9-S13 (1) Main Switch..................9-S13 (2) Air Heater Relay................9-S14 [3] AIR HEATER..................9-S15 [4] STARTER MOTOR ................9-S15 [5] ALTERNATOR ..................9-S17...
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M108S, WSM ELECTRICAL SYSTEM 1. TROUBLESHOOTING Reference Symptom Probable Cause Solution Page All Electrical Battery discharged or defective Recharge or replace 9-S9 Equipments Do Not Battery positive cable disconnected or Repair or replace 9-S8 Operate improperly connected Battery negative cable disconnected or...
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M108S, WSM ELECTRICAL SYSTEM AIR HEATER Reference Symptom Probable Cause Solution Page Air Heater Does Not Slow blow fuse blown Replace 9-S11 Heat Air heater relay defective Replace 9-S25 Air heater defective Replace 9-S15 W1010808 CHARGING SYSTEM Charging Lamp Does...
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M108S, WSM ELECTRICAL SYSTEM LIGHTING SYSTEM Reference Symptom Probable Cause Solution Page Head Light Does Not Fuse blown Replace 9-S11 Light Bulb blown Replace – Wiring harness disconnected or improperly Repair or replace – connected (between main switch B terminal and...
M108S, WSM ELECTRICAL SYSTEM 2. SERVICING SPECIFICATIONS STARTER MOTOR Item Factory Specification Allowable Limit Commutator O.D. 32.0 mm 31.4 mm 1.26 in. 1.24 in. Mica Undercut 0.50 to 0.80 mm 0.2 mm 0.020 to 0.031 in. 0.08 in. Brush Length 18.0 mm...
M108S, WSM ELECTRICAL SYSTEM 3. TIGHTENING TORQUES Tightening torques of screws, bolts and nuts on the table below are especially specified. (For general use screws, bolts and nuts : Refer to “5. TIGHTENING TORQUES” at “G.GENERAL” section.) Item N·m kgf·m lbf·ft...
M108S, WSM ELECTRICAL SYSTEM 4. CHECKING AND ADJUSTING [1] BATTERY AND FUSE (1) Battery Battery Voltage 1. Stop the engine and turn the main switch off. 2. Connect the COM (−) lead of the voltmeter to the battery's negative terminal post and the (+) lead to the positive terminal post, and measure the battery voltage.
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M108S, WSM ELECTRICAL SYSTEM Battery Condition Indicator 1. Check the battery condition by reading the indicator (2). State of indicator display Specific gravity of electrolyte and quality of Green electrolyte are both in good condition. Black Needs charging battery White...
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M108S, WSM ELECTRICAL SYSTEM Battery Storage 1. When shutting down the tractor for long periods of time, remove the battery from the tractor, store the battery in a well ventilated placed where it is not exposed to direct sunlight. 2. Since the battery self-discharges by approx. 0.5 % per day even in storage, it must be once every two months in cold season.
M108S, WSM ELECTRICAL SYSTEM (2) Checking Fuse Replacing Fuse 1. The tractor electrical system is protected from potential damage by fuses. A blown fuse indicates that there is an overload or short somewhere in the electrical system. 2. If any of the fuses should blow, replace with a new one of the same capacity.
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Heater (25) 60 A Head light (26) 60 A Air conditioner (Fan motor) (27) 10 A Common rail system (CRS) power (M108S) (28) 15 A Seat 20 A 15 A Spare 10 A [A] Air Suspension Seat Type (If Equipped)
M108S, WSM ELECTRICAL SYSTEM [2] MAIN SWITCH (1) Main Switch Preparation 1. Remove the meter panel and the main switch connectors after turning the main switch off. 2. Perform the following checking. (1) Main Switch W1016075 Connector Voltage 1. Measure the voltage across the connector B terminal and chassis.
M108S, WSM ELECTRICAL SYSTEM Main Switch at START Position 1. Turn and hold the main switch at the START position. 2. Measure the resistances across the B terminal and the IG1 terminal, and across the B terminal, and the ST terminal.
M108S, WSM ELECTRICAL SYSTEM [3] AIR HEATER Connector Voltage 1. Disconnect the wiring white color lead (2) from air heater (1) after turning the main switch OFF. 2. Make sure that the shuttle shift lever is in the NEUTRAL position and the PTO control lever to OFF position.
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M108S, WSM ELECTRICAL SYSTEM Motor Test CAUTION • Secure the starter to prevent it from jumping up and down while testing the motor. 1. Disconnect the battery negative cable from the battery. 2. Disconnect the battery positive cable and the leads from the starter C terminal (1).
M108S, WSM ELECTRICAL SYSTEM [5] ALTERNATOR Preparation 1. Disconnect the 2P connector (3) from alternator after turning the main switch OFF. 2. Perform the following checkings. (1) B Terminal (3) 2P Connector (2) Alternator W1030485 Connector Voltage 1. Turn off the main switch. Measure the voltage between the B terminal (1) and the chassis.
M108S, WSM ELECTRICAL SYSTEM [6] METER PANEL (1) Setting Mode (Select the PTO Display Mode Switching, Tractor Model Select and Entering Travel Speed Coefficient) CAUTION • To perform the meter panel, the operator must be seated on the tractor. LCD Monitor Indication (Setting Mode)
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M108S, WSM ELECTRICAL SYSTEM PTO Speed Display Mode Switching (Setting Mode) 1. While pressing the PTO/Hour meter select switch (1), turn the key switch to “ON” position. The current numerical code starts flashing. 2. Each time the PTO/Hour meter select switch (1) is pressed, the code changes in the order of [3] →...
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M108S, WSM ELECTRICAL SYSTEM Entering Traveling Speed Coefficient [Example : Entering 4953 mm] 1. While pressing the traveling speed select switch (2), turn the key switch to “ON” position. The setting of the current tire’s circumference is displayed in inches or millimeters. The highest- digit numeral starts flashing.
M108S, WSM ELECTRICAL SYSTEM [7] LIGHTING SWITCH AND FLASHER UNIT (1) Lever Combination Switch Checking Connector Voltage 1. Disconnect the lever combination switch connector (1). 2. measure the voltage with voltmeter across the connector terminal B1 and chassis, across the terminal B2 and chassis.
M108S, WSM ELECTRICAL SYSTEM (2) Hazard Switch Checking Connector Voltage 1. Connect the battery negative code, then measure the voltage with a voltmeter across the terminal a and chassis. 2. If the voltage differ from the battery voltage, the wiring harness is faulty.
M108S, WSM ELECTRICAL SYSTEM (3) Flasher Unit Connector Voltage 1. Disconnect the flusher unit connector. 2. Measure the voltage with voltmeter across the wiring harness connector's terminal 5 and chassis. 3. If the voltage differs from the battery voltage, the wiring harness or fuse is faulty.
M108S, WSM ELECTRICAL SYSTEM (4) Work Light Switch Preparation 1. Remove the outer roof, and disconnect the working light switch connector (1) from the switch (2) connector. 2. Perform the following checkings “Connector Voltage” and “Working Light Switch”. (1) Working Light Switch Connector...
M108S, WSM ELECTRICAL SYSTEM [8] RELAYS (1) Starter Relay and Heater Relay Checking Connector Voltage 1. Measure the voltage with a voltmeter across the battery terminal and chassis as table below. 2. If the voltage differs from the battery voltage, the wiring harness or fuse is faulty.
M108S, WSM ELECTRICAL SYSTEM (2) Relays (PTO Safety, Work Light, Auxiliary Power and A/C Compressor) Functional Check NOTE • The relays described here are used same ones so that these are interchangeable. 1. Apply battery voltage across the terminals a and c, and check for continuity across the terminals d and e.
M108S, WSM ELECTRICAL SYSTEM [9] SWITCH, SENSOR, INJECTOR, BUZZER AND SOLENOID VALVE (1) Sensor and Injector (Common Rail System) Coolant Temperature Sensor 1. Measure the resistance between terminal (+) and (−). 15.04 kΩ at −20 °C (−4 °F) Coolant temperature 2.45 kΩ...
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M108S, WSM ELECTRICAL SYSTEM Rail Pressure Sensor 1. Refer to “Diagnosis Manual”. NOTE • Do not remove the rail pressure sensor (2) from the common rail (1). (1) Common Rail (2) Rail Pressure Sensor W1041558 Fuel Temperature Sensor 1. Measure the resistance between terminal (+) and (−).
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M108S, WSM ELECTRICAL SYSTEM Injector and Injector Harness Continuity 1. Check the continuity between terminal (+) and (−) of each injector harness from the coupler of injector harness. 2. If it is not conductive, check the continuity of harness itself and injector itself.
M108S, WSM ELECTRICAL SYSTEM (2) Swing Shift Monitor Switch (LO and HI) 1. Remove the monitor switch (1), (2). 2. Check the continuity with an ohmmeter across switch terminals. 3. If it does not conduct or any value is indicated when the switch is pushed, the switch is faulty.
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M108S, WSM ELECTRICAL SYSTEM Swing Shift Switch 1. Remove the Hi-Lo touch shift switch (1) connector. 2. Check the continuity with a ohmmeter across the 2 terminal to the 1 terminal, and across the 2 terminal to the 3 terminal.
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M108S, WSM ELECTRICAL SYSTEM HI-LO Shift Solenoid Valve 1. Disconnect the connector (1). 2. Measure the resistance with an ohmmeter across the 1 terminal to the chassis, and the 2 terminal to the chassis. 3. If infinity is indicated, the solenoid valve is faulty.
M108S, WSM ELECTRICAL SYSTEM (3) Dual Speed (DS Model Only) Dual Speed Indicator 1. Remove the indicator (1) from the side panel. 2. Check the continuity with an ohmmeter across the indicator terminals. 3. If value is indicated, the bulb is faulty.
M108S, WSM ELECTRICAL SYSTEM Dual Speed Solenoid Valve 1. Disconnect the wire harness connector (1). 2. Measure the resistance with an ohmmeter across the 1 terminal on the connector (2) and chassis. 3. If infinity is indicated, the solenoid valve is faulty.
M108S, WSM ELECTRICAL SYSTEM Parking Brake Switch Continuity 1. Check the continuity with an ohmmeter across the switch terminals. 2. If it does not conduct or any value is indicated when the switch is pushed, the switch is faulty. 3. If infinity is not indicated when the switch is released, the switch is faulty.
M108S, WSM ELECTRICAL SYSTEM (6) Fuel Level Sensor Checking Fuel Level Sensor 1. Remove the fuel level sensor from the fuel tank. 2. Measure the resistance with an ohmmeter across the terminal a and terminal b. 3. If the measurement is not indicated, the sensor is faulty.
M108S, WSM ELECTRICAL SYSTEM (7) Engine Oil Pressure Switch Engine Oil Pressure Switch Panel Board and Wiring Harness 1. Disconnect the lead (2) from the engine oil pressure switch (1) after turning off the main switch. 2. Turn on the main switch and connect a jumper lead from the lead to the chassis.
M108S, WSM ELECTRICAL SYSTEM (8) PTO Switch PTO Switch 1) Wiring Harness 1. Disconnect the leads from the PTO switch (1). 2. Connect the wiring harness lead terminals to each other and turn the main switch ON. 3. If the indicator do not light, the fuse, wiring harness or bulb is faulty.
M108S, WSM CABIN 1. AIR CONDITIONING SYSTEM [1] STRUCTURE (1) Heater Hose (4) Outer Roof (7) High Pressure Pipe and Low (9) Condenser (2) Air Conditioner Unit (5) Inner Air Filter Pressure Pipe (10) Compressor (3) Control Unit (6) Fresh Air Filter...
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M108S, WSM CABIN The machine is equipped with a thin large-capacity air conditioner with outside air intake. The air through the inside air filter (9) as well as the outside air filter (4) and the roof (8) reaches the air conditioner unit (1). The air is cooled and dehumidified by this unit.
M108S, WSM CABIN [2] COMPRESSOR The vane type compressor installed on this cabin is composed of a cylinder (1) with an oval cross section and a rotor (2) with five vanes (3). The vane type compressor is provided with two suction ports and two discharge ports respectively.
M108S, WSM CABIN [3] AIR FLOW Air in the CAB and fresh air introduced into CAB flow as shown below. Adjust the nine air ports to obtain the desired condition. IMPORTANT • Do not pour water directly into the fresh air port while washing the vehicle.
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M108S, WSM CABIN Door air outlet The door air outlets can be adjusted to direct air on to the door window or the foot area. (1) Door Air Outlet (A) Open (B) Shut (C) Door Window (D) Foot Area W1013941...
M108S, WSM CABIN [5] CONTROL PANEL Control panel switch • Mode Switch (2) (a): Air is blown from only the face air outlets. (b): Air is blown from the front, face and door air outlets. (c): Air is blown from the front and door air outlets.
M108S, WSM CABIN [6] OPERATION Heating 1. Set the mode switch (2) to the (a), (b), (c) position. 2. Set the recirculation / fresh air selection lever (4) to the “FRESH AIR” position. To raise the temperature quickly, this lever “RECIRCULATION”...
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M108S, WSM CABIN Cooling or dehumidifying-heating 1. Set the mode switch to the (a) or (b) position. 2. Set the recirculation / fresh air selection lever to the “FRESH AIR” position. To fall the temperature in the quickly, this lever “RECIRCULATION”...
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M108S, WSM CABIN Defrosting or demisting To defrost or demist the windshield, take the following steps. 1. Set the mode switch (2) to the (c) position. 2. Open the front air outlet, door air outlet direct it to the windshield.
M108S, WSM CABIN [7] ELECTRICAL SYSTEM (1) Electrical Circuit (1) Temperature Control Dial (5) Compressor Relay (9) Blower Motor Switch (13) Mode Select Switch (2) Mode Switch (6) Blower Relay (10) Compressor Magnet Clutch (14) Motor Drive Circuit (3) Thermostat...
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SERVICING CONTENTS 1. TROUBLESHOOTING ..................10-S1 2. SERVICING SPECIFICATIONS ..............10-S5 3. TIGHTENING TORQUES ................10-S6 4. PRECAUTIONS AT REPAIRING REFRIGERANT CYCLE ......10-S7 [1] HANDLING OF SERVICE TOOLS............10-S8 (1) Manifold Gauge Set ................10-S8 (2) Refrigerant Charging Hose .............10-S10 (3) Vacuum Pump Adaptor..............10-S11 (4) Electric Gas Leak Tester..............10-S11 (5) Can Tap Valve ................10-S12 (6) T-joint ....................10-S12 (7) R134a Refrigerant Recover and Recycling Machine ......10-S12...
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M108S, WSM CABIN 1. TROUBLESHOOTING COMPRESSOR Reference Symptom Probable Cause Solution Page Noisy Bearing of compressor worn or damaged Replace 10-S39 (Compressor ON) Valves in compressor damaged Replace 10-S39 Belt slipping Adjust or replace G-29 Compressor bracket mounting screws loosen Tighten –...
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M108S, WSM CABIN AIR CONDITIONING SYSTEM (Continued) Reference Symptom Probable Cause Solution Page Insufficient Cooling Belt slipping Adjust or replace G-29 (Compressor Does Magnetic clutch defective Repair or replace 10-S39, 40 Not Rotate Properly) Compressor defective Replace 10-S39, 40 Insufficient Cooling...
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M108S, WSM CABIN AIR CONDITIONING SYSTEM (Continued) Reference Symptom Probable Cause Solution Page Insufficient Cooling Refrigerant too short Check with manifold 10-S21 (Hi-pressure Level is gauge Too Low) Low-pressure pipe in trouble (Cracked or Replace – clogged) Insufficient Cooling Refrigerant overcharged...
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M108S, WSM CABIN WINDSHIELD WIPER Reference Symptom Probable Cause Solution Page Windshield Wiper Fuse blown (Short-circuit, burnt component Correct cause and – Does Not Operate inside motor or other part for operation) replace Wiper motor defective (Broken armature, worn Replace...
M108S, WSM CABIN 2. SERVICING SPECIFICATIONS Item Factory Specification Allowable Limit A/C Compressor Magnet Clutch Airgap 0.30 to 0.65 mm – 0.012 to 0.025 in. 3.0 to 4.0 Ω Magnet Clutch Stator Coil Resistance – Refrigerating Cycle Pressure 0.15 to 0.20 MPa –...
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M108S, WSM CABIN 3. TIGHTENING TORQUES Tightening torques of screws, bolts and nuts on the table below are especially specified. (For general use screws, bolts and nuts : Refer to “5. TIGHTENING TORQUES” at “G. GENERAL” section.) Item N·m kgf·m lbf·ft...
M108S, WSM CABIN 4. PRECAUTIONS AT REPAIRING REFRIGERANT CYCLE When checking or repairing the air conditioning system, the following precautions and rules must be observed. And it is of first importance that no other personnel than a well-trained serviceman should be allow to handle the refrigerant.
M108S, WSM CABIN (Reference) Replacing Parts Replenish Quantity Brand Name 20 cc Condenser 0.021 U.S.qts 0.018 Imp.qts 20 cc Evaporator 0.021 U.S.qts ND-ACEITE 8<PÁG* oil> 0.018 Imp.qts 10 cc Receiver 0.011 U.S.qts 0.009 Imp.qts *PAG : Polyalkyleneglycol (Synthetic oil) W1012709...
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M108S, WSM CABIN When LO Valve is Closed and HI Valve is Opened Two circuits are established. Port (C) → HI pressure gauge (2) → Port (B) → Port (D) (Schrader valve must be opened) Port (A) → LO pressure gauge (1) NOTE •...
M108S, WSM CABIN (2) Refrigerant Charging Hose The charging hoses are classified into three colors. Each charging hose must be handled as follows : • The air conditioner manufacture recommends that the blue hose (3) is used for the LO pressure side (suction side), the green hose (5) for refrigeration side (center connecting port) and the red hose (4) for HI pressure side (discharged side).
M108S, WSM CABIN (3) Vacuum Pump Adaptor Objective of the Vacuum Pump Adaptor 1. After vacuum has been created in the air conditioning cycle, when the vacuum pump is stopped, since there is vacuum in hoses within the gauge manifold, the vacuum pump oil flows back into the charging hose.
M108S, WSM CABIN (5) Can Tap Valve The can tap valve that is used to charge the refrigerant into the air conditioning system, should be used as follows : 1. Before putting the can tap valve on the refrigerant container, turn the handle (1) counterclockwise till the valve needle is fully retracted.
M108S, WSM CABIN 5. CHECKING AND CHARGING REFRIGERANT CYCLE [1] CHECKING WITH MANIFOLD GAUGE IMPORTANT • The gauge indications described in the following testing are those taken under the same condition, so it should be noted that the gauge readings will differs somewhat with the ambient conditions.
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M108S, WSM CABIN Insufficient Refrigerant 1. Symptoms seen in refrigerating cycle - Both LO and HI pressure side (1), (2) pressures too low. LO pressure side (1) : 0.05 to 0.10 MPa (0.5 to 1.0 kgf/cm , 7.1 to 14.2 psi) HI pressure side (2) : 0.69 to 0.98 MPa...
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M108S, WSM CABIN Air Entered in the Cycle 1. Symptoms seen in refrigerating cycle - Both LO and HI pressure side (1), (2) pressures too high. LO pressure side (1) : 0.20 to 0.35 MPa (2.0 to 3.5 kgf/cm , 28.4 to 49.8 psi) HI pressure side (2) : 1.96 to 2.45 MPa...
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M108S, WSM CABIN Refrigerant Fails to Circulate 1. Symptoms seen in refrigerating cycle - LO pressure side (1) pressure is vacuum and, HI pressure side (2) is low pressure. LO pressure side (1) : Vacuum HI pressure side (2) : 0.49 to 0.59 MPa (5 to 6 kgf/cm , 71.2 to 85.3 psi)
M108S, WSM CABIN Faulty Compression of Compressor 1. Symptoms seen in refrigerating cycle - LO pressure side (1) : 0.39 to 0.59 MPa (4 to 6 kgf/cm , 56.9 to 85.3 psi) - HI pressure side (2) : 0.69 to 0.98 MPa (7 to 10 kgf/cm , 99.6 to 142.2 psi)
M108S, WSM CABIN (2) Evacuating the System Evacuating the System 1. Discharge refrigerant from the system by R134a refrigerant recovery and recycling machine. (Refer to “(1) Discharging the Refrigerant” in this section.) 2. Connect the charging hose (4) (red) to the HI pressure side charging valve and connect the charging hose (5) (blue) to the LO pressure side charging valve.
M108S, WSM CABIN (3) Charging the Refrigerant Charging an Empty System (Liquid) This procedure is for charging an empty system through the HI pressure side with the refrigerant in the liquid state. CAUTION • Never run the engine when charging the system through the HI pressure side.
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M108S, WSM CABIN Charging an Empty or Partially Charged System (Vapor) This procedure is to charge the system through the LO pressure side with refrigerant in the vapor state. When the refrigerant container is placed right side up, refrigerant will enter the system as a vapor.
M108S, WSM CABIN (4) Checking Charge Refrigerant Amount After charging the refrigerant, check for amount of charging refrigerant as follows. NOTE • The pressure on the following checking is the gauge indications at ambient temperature 30 °C (86 °F), so it should be noted that the pressure will differ some what with the ambient temperature.
M108S, WSM CABIN 6. CHECKING, DISASSEMBLING AND SERVICING [1] CHECKING AND ADJUSTING (1) Compressor Operation of Magnetic Clutch 1. Start the engine. 2. Check whether abrasion of abnormal noise is heard when only the magnetic clutch pulley is running while the A/C switch is turned off.
M108S, WSM CABIN (2) Air Conditioner Unit Connector Voltage (Blower Relay, Compressor Relay) 1. When turning on the main switch, voltage across the 1 terminal and chassis should be approx. battery voltage. 2. The voltage across the d terminal and chassis should be approx.
M108S, WSM CABIN (3) Blower Switch Connector Voltage 1. Disconnect the blower switch 4P connector. 2. Turn the main switch “ON” position. 3. Measure the voltage with a voltmeter across the connector 3 terminal and 4 terminal. 4. If the voltage differs from the battery voltage, the wiring harness, A/C relay, fuse or main switch is faulty.
M108S, WSM CABIN (4) Blower Motor Blower Motor Test 1. Remove the outer roof. 2. Turn the blower motor (1) by hand and check whether it turns smoothly. 3. Disconnect the connector (2) of blower motor (1). 4. Connect a jumper lead from battery (3) positive terminal to connector B terminal.
M108S, WSM CABIN (6) A/C Switch Connector Voltage 1. Disconnect the A/C switch 3P connector. 2. Turn the main switch “ON” position. 3. Measure the voltage with a voltmeter across the connector 1 terminal and terminal. 4. If the voltage differs from the battery voltage, the wiring harness, A/C relay or fuse is faulty.
M108S, WSM CABIN (7) Mode Switch Mode Switch Check 1. Disconnect the mode switch 4P connector. 2. Check the continuity through the switch with an ohmmeter. 3. If the continuity specified below is not indicated, check the switch. Terminal Position...
M108S, WSM CABIN (9) Temperature Motor Temperature Motor Check 1. Confirm whether the temperature control dial (2) is defective. (Refer to “(8) Temperature Control Dial” in this section.) 2. Turn the main switch “ACC” position. 3. Turn the blower switch (3) at 1 position.
M108S, WSM CABIN (11) A/C Pressure Switch HI Pressure Side 1. Connect the manifold gauge (5) to compressor as following procedure. Close the HI and LO pressure valves (3), (4) of manifold gauge tightly, and connect the charging hoses (red and blue) (6), (7) to the respective compressor service valves.
M108S, WSM CABIN LO Pressure Side 1. Disconnect 2P connector of pressure switch. 2. Measure the resistance with an ohmmeter across the connector terminals. 3. If 0 ohm is not indicated at normal condition, there is no refrigerant in the refrigerating cycle because gas leaks or pressure switch is defective.
M108S, WSM CABIN Wiper Switch 1. Check the continuity through the switch with an ohmmeter. 2. If the continuity specified below are not indicated, the switch is faulty. Terminal Position WASH I WASH II (1) Front Wiper Switch Connector W1046557...
M108S, WSM CABIN [2] DISASSEMBLING AND ASSEMBLING (1) Separating Cabin from Tractor Draining Coolant CAUTION • Never remove the radiator cap until coolant temperature is well below its boiling point. Then loosen cap slightly to the stop to relieve any excess pressure before removing cap completely.
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M108S, WSM CABIN Preparation 2 1. Remove the battery (1). 2. Remove the ECU cover (2). 3. Remove the ECU mounting screws and ECU (3). NOTE • Take care not to damage to ECU. (1) Battery (3) ECU (2) ECU Cover...
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M108S, WSM CABIN Preparation 3 Without discharging the refrigerant from system 1. Remove the air condenser slide stopper (1) and slide out the air condenser (2). 2. Loosen the lock nut (6) and adjusting screw (5) then remove the air compressor belt (8).
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M108S, WSM CABIN Preparation 4 1. Remove the brake oil tank (1). 2. Remove the power steering delivery hose (2). 3. Remove the joint shaft (3). (When reassembling) 22 to 27 N·m Power steering turning Tightening torque 2.2 to 2.8 kgf·m hose retaining nut 16 to 20 lbf·ft...
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M108S, WSM CABIN Preparation 6 1. Remove the seat (1) and floor seat cover (2). 2. Remove the floor mat (3) and inspection plate under the floor mat. 3. Disconnect the main shift rod 2 (5). 4. Disconnect the select wire (4).
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M108S, WSM CABIN Preparation 7 1. Remove the differential lock rods (1), (2). 2. Disconnect the draft control rod (3) and position control rod (4). 3. Remove the auxiliary control valve cable (5). 4. Remove the parking brake cable (6).
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M108S, WSM CABIN Dismounting Cabin 1. Set the cabin dismounting tool (2). 2. Remove the cabin mounting bolts and nuts (1). 3. Dismounting the cabin from tractor body. (When reassembling) 123.6 to 147.1 N·m Cabin mounting screws Tightening torque 12.6 to 15.0 kgf·m and nuts 91.1 to 108.5 lbf·ft...
M108S, WSM CABIN (2) Removing Compressor Assembly Compressor Assembly 1. Discharge the refrigerant from the system. (Refer to “(1) Discharging the Refrigerant” in this section.) 2. Disconnect the low pressure pipe (suction) (1) and high pressure pipe 1 (discharge) (2) from the compressor, then cap the open fitting immediately to keep moisture out of the system.
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M108S, WSM CABIN Hub Plate 1. Three stopper bolts (1) are set in stopper magnet clutch (2) at the position corresponding to the shape of compressor. (Refer to “8. SPECIAL TOOLS” at “G. GENERAL” section.) 2. The stopper magnet clutch (2) is hung on hub plate (3) and it is fixed that the compressor rotates.
M108S, WSM CABIN (3) Removing Air Conditioner Unit Air Conditioning Unit 1. Remove the unit cover (1). 2. Disconnect the heater hoses (6). 3. Disconnect the cooler pipe (liquid) (2) and cooler pipe (suction side) (3). 4. Remove the five screws and take off the air conditioning unit.
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M108S, WSM CABIN High Pressure Pipe 1, 2 and Low Pressure Pipe 1. Disconnect the low pressure pipe (2) and high pressure pipe 1 (1) from the compressor (3), then cap the open fittings immediately to keep moisture out of the system.
M108S, WSM CABIN High Pressure and Low Pressure Pipes 1. Remove the outer roof. 2. Disconnect the pressure switch (1) connector. 3. Disconnect the high pressure pipe 2 (2), then cap the open fitting immediately to keep moisture out of the system.
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M108S, WSM CABIN Heater Hoses 1. Disconnect the heater hoses (1), (2), and take out them under the cabin. (When reassembling) • Note the inlet hose and outlet hose. (1) Heater Hose 1 (2) Heater Hose 2 W1030123 Inner Covers 1.
NOTE • Sika Tack-Ultrafast and cleaner No. 1 are made by Sika Corporation. • These materials can't be provided by Kubota Corporation. • Therefore, please find the local made equivalent materials in your country and use them when you need.
M108S, WSM CABIN Before Replacing Windshields (3) 1. Check that the glasses are not damaged and cracked. 2. Turn over the glass and clean this surface of the glass by Sika- cleaner No. 1. 3. The cleaning area of the rear surface is indicated “A” in the figure left.
M108S, WSM CABIN Rear Wiper Motor (Option) 1. Remove the wiper motor cover (5). 2. Disconnect the rear wiper motor 4P connector (2). 3. Remove the wiper arm mounting nut (4) and wiper arm (6). 4. Remove the wiper link cap (3) and nut.
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EDITOR : KUBOTA FARM & INDUSTRIAL MACHINERY SERVICE, LTD. 64, ISHIZU-KITAMACHI, SAKAI-KU, SAKAI-CITY, OSAKA, 590-0823, JAPAN PHONE : ( 81 ) 72-241-1129 : ( 81 ) 72-245-2484 E-mail : ksos-pub@kubota.co.jp KUBOTA Corporation Printed in Japan 2007. 05, S, E I , E I , e Code No.9Y111-00720...
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Questions and answers
2017 m108s. When shifting into first or second, tractor kicks out of gear like it's not fully engaging. 3 and 4 work as it should. Is this an adjustment issue or something more. 3200 hrs
A Kubota M108S kicking out of gear when shifting into first or second could be due to several possible causes. It may be an adjustment issue, such as improper linkage settings or wear in the shift mechanism. However, it could also indicate a more serious problem, such as worn or damaged gears, synchronizers, or internal transmission components. Checking the shift linkage for proper adjustment and wear is a good first step. If the issue persists, internal transmission inspection may be required.
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@Mr. Anderson Thanks!