Johnson 60hp bad compresssion in one cylinder

B

bama121212

Recruit
Joined
May 30, 2009
Messages
1
I have a 1987 Johnson 60hp (3 cylinder) that has 30psi compression in the top cylinder, 110psi in the middle and 120psi in the bottom cylinder. It stalls when putting into gear (forward and reverse) and when you can get it in gear without stalling it will only run up to about 4000 RPM. I would appreciate any suggestions on the logical progression of things I would check and do. Naturally I would want to check and do the easiest and least expensive things first and hopefully I can avoid a total rebuild. I'm new to outboard motors, so any help and suggestions I can get would be appreciated.
 
T

tx1961whaler

Vice Admiral
Joined
May 31, 2008
Messages
5,197
Re: Johnson 60hp bad compresssion in one cylinder

You're gonna have to pull the cylinder head and inspect the cylinder walls. If that's OK then put a new head gasket after making sure the head is still flat.
Was the engine overheated? That's the usual cause, if it is a head gasket issue. If the cylinder walls are scored up badly, then that's a whole different issue....
 
kenmyfam

kenmyfam

Supreme Mariner
Joined
Aug 10, 2006
Messages
14,398
Re: Johnson 60hp bad compresssion in one cylinder

Start with the heads and see what you got. See how those cylinder walls look, the piston tops and the head itself.
 
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