2. MAINTENANCE
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Adjust if the valve clearance is out of the service limit.
Measure the valve clearance in the cold the gasoline engine state.
Adjusting valve clearance
Valve clearance adjustment method: Loose the locking nut, turn the adjusting nut to get the
correct valve clearance. Screw down the locking nut
Valve clearance
IN 0.15±0.02mm
EX 0.20±0.02mm
Adjusting nut
Valve clearance
Screw down
Small
Screw off
Big
CAUTION:
Clearance too big: Intake and exhaust valve opening delay will shorten the intake and
exhaust time, lower the opening height of the valve and change normal distributing
phase to result in power lowering from the intake lack and exhaust uncompleted.
Furthermore, also make vale train parts knock increasing and wearing quick.
Clearance too small: After running, gasoline engine parts will be heated to expand and
push the valve open, making the gasoline engine closing not tight and result in leaking,
power lowering, serious carbon deposit or burn on the valve surface, even valve
impacting the piston.
VALVE ADJUSTING NUT
VALVE LOCKED NUT
