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Compression 1990 70hp

J

Jeff67

Member
1 Cylinder 118lbs. 2 Cylinder 98lbs. 3 Cylinder 94lbs. Johnson 1990 70hp
The engine was running great now it is running really rough. Number 1 plug looks normal with little oil on it. Number 2 looks dry. Number 3 looks a bit wetter than number 1 cylinder. Is it time for a new motor? I heard about a Amsoil Foam product that you squirt into the carbs while running and it is supposed help with cleaning the cylinders and evening up the compressions.
Your thoughts appreciated
 
Take the cylinder head off for a look.----And does the tell tale fitting come off the side of the block ?-----Or was it moved to the top of the block as per a 1994 service bulletin?
 
I can not believe that folks are reluctant to remove a cylinder head to inspect cylinder walls.------Head gaskets are cheap compared to electronic parts.------Folks will install big $$$ stators , powerpacks / triggers on advice of a neighbor in the hope of finding the magic fix !
 
Are you directing your last reply to me? I am one that is never afraid of working on anything but there comes a time when it is not worth trying to salvage a power head. I would think that with my compression issue, I might be at that point. That's why I asking.
 
Take the head off and have a look in there ----Inspection is what needs to be done.----No point in guessing.-----Maybe head bolts were never checked for torque.----Remember no one here can see , feel or hear your motor !
 
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