Yamaha F225A Service Manual page 352

TRBL
SHTG
Compression pressure
Check that there is no secondary air intake on the contact surfaces of
the intake manifold and crankcase.
Is there air
intake?
No
Check the compression pres-
sure of the combustion chamber.
Symptom: The engine idle speed is not steady, but increases or decreases.
• Check the intake manifold.
• Check the air intake system.
• Check the ignition system.
Check the operation of the
throttle cable and throttle link.
Good operat-
ing condition?
Yes
Check the synchronization of
the throttle valve.
Are the throt-
tle valves
synchronize?
No
Synchronize the throttle valves.
9-53
Troubleshooting
Yes
Replace the respective seals.
No
Adjust the throttle cable and
throttle link.
Yes
Check the ignition timing.
Check the engine using the
Yamaha Diagnostic System.
Out of
specification?
Yes
Check the second-
ary air intake on the
O-ring and manifold
No
plate, idle speed
control hose, and
the gaskets of the
vacuum check bolts.
69J3D11