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Cordless Chain Saw 115mm (4-1/2) ONCEPT AND MAIN APPLICATIONS Models BUC121 and BUC122 have been developed as the first Makita cordless chain saws powered by 3.0Ah Li-ion battery. Features higher operation efficiency and more convenience than the current 12V Model UC120D.
To protect parts and product from unusual abrasion; 1) apply 7g of Makita grease N No. 2 (Part No. 181573-3: Grease vessel 93g) to Gear room. Note: Be sure to apply a little amount of the above grease to the inner periphery of Crank.
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P 3 / 8 epair [3] DISASSEMBLY/ ASSEMBLY (cont.) [3]-2. Disassembling/ Assembling Gear Section DISASSEMBLING 1) Remove Stop ring E-8 from Spindle then remove Sprocket 9 and Lock washer 12. 2) Loosen four 4x18 Tapping screws (Fig. 3) then strike Spindle end using plastic hammer. (Fig. 4) Bearing housing can be removed.
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2) Pull off Crank and check if O ring 1.5 on its end of pin portion has damaged or not. 3) Pour approx. 30cc of Makita genuine chain oil (Refer to LUBRICANT) or commercial oil VG32-100 to Oil tank. Rise and fall Crank by hand while checking if Chain oil is delivered from chain oil exit designated by arrow in Fig.
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P 5 / 8 epair [3] DISASSEMBLY / ASSEMBLY (cont.) [3]-5. Disassembling/ Assembling Filter in Handle R DISASSEMBLING Fig. 11 1) Strike the center of Push nut gently using Phillips screwdriver No.2 (Fig. 11), Phillips Push nut can be removed, and Filter can be picked out of chain oil exit of screwdriver No.
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P 6 / 8 epair [3] DISASSEMBLY / ASSEMBLY [3]-6. Disassembling/ Assembling Motor Section (cont.) Fig. 14 ASSEMBLING Notch of Yoke 1) When mounting Yoke on Motor housing R, fit the notch of Yoke into the protrusion of Motor housing R. (Fig. 14) 2) Insert Armature gear shaft to gear room of Handle R, and fix Motor housing to Handle R by tightening 4x30 Tapping screws (4 pcs.).
P 7 / 8 ircuit diagram Fig. D-1A For BUC121, BUC122 Color index of lead wires' sheath Switch Black White Terminal Endbell complete Fig. D-1B For --- Color index of lead wires' sheath Switch Black White Yellow Terminal Endbell complete Controller iring diagram Fig.
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P 8 / 8 iring diagram Fig. D-3A For BUC121, BUC122 Switch Lead wire holders Terminal unit Motor housing Lead wire holders Fix the following Lead wires with Lead wire holders. 1) Lead wires for Endbell complete 2) Lead wires for connecting Switch and Terminal unit Fig.