Compression Pressure Measurement - Yamaha F15MHX Manuel D'entretien

INSP
ADJ
b
1
GENERAL
a
377-004
NOTE:
9 Before installing the spark plug, clean the
gasket surface and spark plug surface.
Also, it is suggested to apply a thin film of
anti-seize compound to the spark plug
thread to prevent thread seizure.
9 If a torque wrench is not available, a good
estimate of the correct tightening torque is
to finger tighten a the spark plug and then
tighten it another 1/4 to 1/2 of a turn b.
9 Always use a new spark plug gasket.

Compression pressure measurement

NOTE:
Insufficient compression
result in performance loss.
1. Check:
9 Valve clearance
Out of specification
Refer to "Valve clearance".
2. Start the engine and let it warm up for
several minutes.
3. Turn off the engine.
4. Remove:
9 Spark plug
cC
Before removing the spark plug, use com-
pressed air to blow away any dirt accumu-
lated in the spark plug well to prevent it
from falling into the cylinder.
5. Attach:
9 Compression gauge 1
Compression gauge:
YU-33223
90890-03160
3-19
E
pressure will
Adjust.