Question about compression

[flech01]

Hello<br /><br /> I have a 1976 115hp johnson. I just checked the compression and had 124 on 2 cylnders and 120 on one and 110 on the other. I read in another topic tonight to decarb the engine. What does this mean and how do I do it? Am I sol? <br /><br />Thanks for all you help.

 

[rickdb1boat]

Re: Question about compression

I would do the decarb and take the readings again. You are not that far off on the readings and that may get you right back in the ballpark..<br /><br /> Good Decarb procedure written by trusted member

 

[flech01]

Re: Question about compression

thanks rick

 

[flech01]

Re: Question about compression

Hey <br /><br />One more question. Can bad fuel mixture make it show low compression?

 

[Dhadley]

Re: Question about compression

If the piston was damaged by the bad fuel, sure.

 

[flech01]

Re: Question about compression

Not so much bad fuel as to much oil in mixture.

 

[flech01]

Re: Question about compression

If it turns out to be bad rings can I just cahnge bad rings? Or do I have to bore out and replace pistons.

 

[Dhadley]

Re: Question about compression

Lets decarb and go from there. I'll bet youll like the results. Just go with Ricks advice. You cant go wrong.