Compression Pressure Measurement - Yamaha F100A Service Manual

INSP
ADJ
GENERAL
1
4. Tighten:
Spark plugs
Spark plug:
25 Nm (2.5 m • kg, 18 ft • lb)
NOTE:
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
threads to prevent thread seizure.
If a torque wrench is not available, a good
estimate of the correct tightening torque
for new spark plug(-s) is to finger tighten
a the spark plug and then tighten it
another 1/4 to 1/2 of a turn b.

Compression pressure measurement

CAUTION:
Before removing a spark plug, use com-
pressed air to blow away dirt accumulated
in the spark plug well to prevent it from
falling into the cylinder that is being tested.
1. Check:
Valve clearance
Out of specification → Adjust.
Refer to "Valve clearance adjust-
ment".
2. Warm-up:
Engine
3. Remove:
Spark plug(-s)
4. Install:
Compression gauge 1
(into the spark plug hole)
NOTE:
Use a compression gauge that is used for
automobiles.
3-18
E