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Compression

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ebfbburg

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I have a 1999 70 hp Johnson at times it will not accelerate. I had it rebuilt a few years ago. Been running good. It’s just started this acceleration problem. Sometimes I can fish half a day before it does it. I check compression 83 on top 2 cyclinder 78 on bottom cyclinder. Is that good or bad. Just wondering so what my next move would be. Thank you.
 
First I would test with another gauge.-----Was new water pump impeller installed ?---Oil injection tested ? ----Mixing at 50:1 with good oil ?-----Here , with those numbers I would remove cylinder head to inspect.----Head gaskets are cheaper that throwing electronic bits at a problem motor.
 
racerone said:
First I would test with another gauge.-----Was new water pump impeller installed ?---Oil injection tested ? ----Mixing at 50:1 with good oil ?-----Here , with those numbers I would remove cylinder head to inspect.----Head gaskets are cheaper that throwing electronic bits at a problem motor.
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New water
 
Present the facts and answer the questions in post #2 to help yourself quickly .----.-----Your compression test results indicate a issue there !-----Does spark jump a gap of 3/8" on each lead, yes or no ?----Carburetors stored with fuel in them?----Checked flywheel key ?-----Drained carburetors to check for water ?
 
New gauge first time used. New impeller was installed . Automatic mixing disconnected because that was reason it was rebuilt, not getting enough oil .I mixed it myself now. After rebuilt mixing3 1/2 ounces to gallon to start with now 3 ounces to gallon.
 
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