Cooling System; Maintenance Schedule - Zenoah GZ381 Manuel D'utilisation

To lubricate the needle bearing
Both versions of sprockets have a needle bearing on the
drive shaft, which has to be greased regularly (once a
week).
1. Disengage the chain brake by pulling the front hand
guard against the front handle.
2. Unscrew the two bar nuts and remove the clutch
cover.
3. Lay the product on its side with the clutch drum
facing upwards.
4. Remove the clutch drum and lubricate the needle
bearing using a grease gun. Use a high-quality
bearing grease or engine oil. (Fig. 120)
To examine the cutting equipment for
wear
Do a visual check of the saw chain daily.
1. Make sure that there are no visible cracks in rivets
and links.
2. Examine wheather the saw chain is stiff.
3. Compare the existing saw chain with a new saw
chain to decide wheather the rivets and links are
badly worn.
4. Replace the saw chain if it exhibits any of the
conditions above.
5. Replace the saw chain when the length of the cutting
teeth has worn down to only 4 mm.
To do a check of the guide bar
Do a check of the guide bar regularly.
1. Examine whether there are burrs on the edges of the
bar. Remove burrs with a file if necessary.
2. Examine whether the groove in the bar has become
badly worn. Replace the bar if necessary.

Maintenance schedule

Daily maintenance
Clean the external parts of the prod-
uct and make sure that there is no oil
on the handles.
Do a check of the throttle trigger and
throttle trigger lockout. Refer to
a check of the throttle trigger and
throttle trigger lockout on page 30 .
Make sure that there is no damage
on the vibration damping units.
Clean and do a check of the chain
To do a check of the
brake. Refer to
chain brake on page 30 .
34
Weekly maintenance
Clean the cooling system. Refer to
Cooling system on page 34 .
Do a check of the starter, starter rope
To do
and return spring.
Lubricate the needle bearing. Refer
To lubricate the needle bearing on
to
page 34 .
Remove burrs from the edges of the
guide bar. Refer to
the guide bar on page 34 .
3. Examine whether the tip of the bar is uneven or
badly worn. If a hollow forms on the underside of the
bar tip this is due to running with a slack chain.
4. Turn the bar daily to prolong the life of the bar.

Cooling system

The product is equipped with a cooling system to keep
the working temperature as low as possible. The cooling
system consist of the following components:
• Air intake on the starter.
• Air guide plate.
• Fins on the flywheel.
• Cooling fins on the cylinder.
• Cylinder cover (directs cool air over the cylinder).
(Fig. 121)
Clean the cooling system with a brush once a week or
more often in demanding conditions. A dirty or blocked
cooling system causes the product to overheat which
results in damage to the piston and cylinder.
Centrifugal cleaning system
Centrifugal cleaning means that the air to the carburettor
passes through the starter. Dirt and dust is centrifuged
out by the cooling fan.
(Fig. 122)
In order to maintain operation of the centrifugal cleaning
system it must be regularly maintained. Clean the
following components:
• The air intake on the starter.
• The fins on the flywheel.
• The space around the flywheel.
• The inlet pipe.
• The carburettor compartment.
Monthly maintenance
Do a check of the brake band. Refer
Cooling system on page 34 .
to
Do a check of the clutch centre,
clutch drum and clutch spring.
Clean the spark plug. Refer to
a check of the spark plug on page
32 .
Clean the external parts of the carbu-
To do a check of
rettor.
To do
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