Yamaha 20C Service Manual page 259

TRBL
SHTG
ENGINE IS HARD TO START OR WILL NOT START
Is the piston or cylinder cracked, scratched or
deformed?
Is the piston ring damaged or worn?
Are the oil-seal in good condition?
3
Does the engine stop lanyard switch remain
closed?
Is each connection loose?
Is the spark-plug cracked?
Is the spark-plug type correct?
Is the spark-plug in good condition?
Is the spark-plug gap correct?
Does the spark-plug cap have no leaks?
Is the high-tension cable damaged or leaky?
NO
NO
YES
RE-CHECK
YES
NO
NO
YES
YES
YES
YES
NO
YES
Replace.
YES
Replace.
NO
Replace.
NO
Replace.
YES
Tighten.
YES
Replace.
NO
Replace it with correct type.
(P.3-14)
NO
Replace.
NO
Adjust it. (P.3-14)
NO
Replace.
YES
Replace.
9-4
E