Maintenance - Hitachi CG 24EC (S) Handling Instructions Manual

MAINTENANCE

MAINTENANCE, REPLACEMENT OR REPAIR OF THE
EMISSION CONTROL DEVICES AND SYSTEMS MAY
BE PERFORMED BY ANY NON-ROAD ENGINE REPAIR
ESTABLISHMENT OR INDIVIDUAL.
Carburetor adjustment (Fig. 22)
The carburetor is a precision part that mixes air and fuel, and
it is designed to ensure high performance from the engine.
Before the tool is shipped from the factory, its carburetor is
adjusted during a test run. Only make adjustments if it is
necessary because of environmental conditions (the climate
or atmospheric pressure), the type of fuel, the type of two-
cycle oil, etc.
WARNING
○ Because the carburetor is manufactured with a high
degree of precision, do not disassemble it.
○ For this product, the only setting of the carburetor that
can be adjusted is the idle speed (T).
○ Never start the engine without the complete clutch cover
and tube assembled! Otherwise the clutch can come
loose and cause personal injuries.
T = Idle speed adjustment screw.
Idle speed adjustment (T)
WARNING
○ When the engine is stopped, do not excessively turn
the idle speed adjustment screw (T) in a clockwise
direction. Otherwise, when the engine starts, the cutting
attachment may unexpectedly rotate and cause an
injury.
○ Do not adjust the idle speed adjustment screw (T) for
any reason other than to adjust the idling.
Run the engine while adjusting the idling.
(1) If the engine stops during idling
Start the engine, and slowly turn the idle speed
adjustment screw (T) in a clockwise direction until it is in
a position at which the engine rotates smoothly. At that
time, ensure that the cutting attachment is not spinning.
(2) If the cutting attachment rotates during idling
Slowly turn the idle speed adjustment screw (T) in a
counter-clockwise direction until it is in a position at
which the cutting attachment does not rotate. At that
time, ensure that the rotation of the engine is smooth.
WARNING
If the cutting attachment still rotates after adjustment of
the idle speed adjustment screw (T), immediately stop
the engine and cease use, then contact the nearest
Hitachi Authorized Service Center.
Air fi lter (Fig. 23)
The air fi lter (21) must be cleaned from dust and dirt in order
to avoid:
○ Carburetor malfunctions.
○ Starting problems.
○ Engine power reduction.
○ Unnecessary wear on the engine parts.
○ Abnormal fuel consumption.
Clean the air fi lter daily or more often if working in
exceptionally dusty areas.
Loosen the screw (22), then open the air fi lter cover and
remove the air fi lter (21). Rinse it in warm soap suds.
Check that the fi lter is dry before reassembly.
An air fi lter that has been used for some time cannot be
cleaned completely. Therefore, it must regularly be replaced
with a new one. A damaged fi lter must always be replaced.
Fuel fi lter (Fig. 24)
Remove the fuel fi lter (23) from the fuel tank, and replace it if
it is dirty.
NOTE
A blocked fuel fi lter (23) can prevent the supply of fuel and
cause a rotation malfunction of the engine.
Spark plug (Fig. 25)
The spark plug condition is infl uenced by:
○ An incorrect carburetor setting.
○ Wrong fuel mixture (too much oil in the gasoline)
○ A dirty air fi lter.
○ Hard running conditions (such as cold weather).
These factors cause deposits on the spark plug electrodes,
which may result in malfunction and starting diffi culties. If
the engine is low on power, diffi cult to start or runs poorly at
idling speed, always check the spark plug fi rst.
If the spark plug is dirty, clean it and check the electrode
gap. Re-adjust if necessary. The correct gap is 0.6 mm. The
spark plug should be replaced after about 100 operation
hours or earlier if the electrodes are badly eroded.
NOTE
In some areas, local law requires using a resistor spark
plug to suppress ignition signals. If this machine was
originally equipped with resistor spark plug, use same
type of spark plug for replacement.
Gear case (Fig. 26)
Check gear case or angle gear for grease level about every
50 hours of operation by removing the grease fi ller plug on
the side of gear case.
If no grease can be seen on the fl anks of the gears, fi ll the
gear case with quality lithium based multipurpose grease up
to 3/4. Do not completely fi ll the gear case.
CAUTION
○ Make sure to remove any dirt or grit when attaching the
plug to its original position.
○ Before attempting inspection or maintenance of the gear
case, make sure the case has cooled.
Semi-auto cutting head
Nylon line replacement
1. Remove the case (24) by fi rmly pushing inward the
locking tabs with your thumbs as shown in Fig. 27.
2. After removing the case, take out the reel and discard
the remaining line.
3. Fold the new nylon line unevenly in half as shown in
picture.
Hook the U-shaped end of the nylon line into the groove
(25) on the center partition of the reel.
Wind both halves of the line on the reel in the same
direction, keeping each half of the line on its own side of
the partition. (Fig. 28)
4. Push each line into the stopper holes (26), leaving the
loose ends approx. 10 cm in length. (Fig. 29)
5. Insert both loose ends of the line through the cord guide
(27) when placing the reel in the case. (Fig. 30)
NOTE
When placing a reel in the case, try to line up the stopper
holes (26) with the cord guide (27) for easier line release
later.
6. Place the cover over the case so that the cap locking
tabs (28) on the case meet the long holes (29) on the
cover. Then push the case securely until it clicks into
place. (Fig. 31)
7. The initial cutting line length should be approx. 11–14 cm
and should be equal on both sides. (Fig. 32)
11
English