1989 115 hp 4 cyl. compression low?

[stevefishes]

Checked the compression on my motor at 90 psi on all 4 cyls. Should I contemplate a rebuild? Or just use it the way it is?

 

[oldman570]

Re: 1989 115 hp 4 cyl. compression low?

A compression test should be done with all the plugs removed, fuel line disconnected. and throttle in the WOT position. If it was not done in this fashion try it again. The cylinder needs air to compress and if the carbs were in the idle position the air flow is restricted and the readings will be less than what they really are. As long as all the readings are close to the same, and not more than 10% difference then the motor should be good to run more unless you want to freshen everything up, which is a good off season job. JMO
Oldman570

 

[stevefishes]

Re: 1989 115 hp 4 cyl. compression low?

Thanks for the reply om570, that is exactly how the compression checks were done. Seems like the numbers in other posts are a lot higher. I just bought this boat and motor and I'm trying to get it going without putting a lot of money into it. I'm about at the end of what I can do myself so it's off to the mechanic and see what he says.