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Cylinder cutting out on 1990 Johnson 88hp

M

mark etzler

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" I have a 1990 Johnson 88 hp

" I have a 1990 Johnson 88 hp that surges at slow speeds. All cylinders read between 108 to 118 psi compression. All sparks will jump a 3/8" gap. I had a problem once with the check valve on the gas tank sticking. Is there any way I can determine if all the cylinders are getting enough air/fuel? If I pull the plugs after running, the electrodes are wet. Can you tell me what this indicates? "
 
Surging at slow speeds seems

Surging at slow speeds seems to indicate a fuel problem. Hook up an inductive pick-up timing light one cylinder at a time and look for missing on the ignition. If the spark is steady when the engine misses you need to clean the carburetors.
 
I have overhauled the carbure

I have overhauled the carburetors (they were clean) and checked the spark - it jumps 5/16" on all cylinders. Does the wet spark plugs indicate an overrich air/fuel mixture?
 
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