Low compression on 9.9

[Skooks]

Hi all:<br /><br />I have a 1975 9.9 merc. Both cylinders measure 75 lbs on an accurate gauge. The engines starts and runs very well. Does the low compression indicate that I may need a ring job in the near future?<br /><br />Thanks,<br /><br />Don

 

[Kenny Bush]

Re: Low compression on 9.9

Check your manual for compression specs. I have seen several people run them that low, as long as the cylinders are within 10% of each other, it is balanced enough to run.... Did you do a compression test with the engine warmed up? 75 lbs seems on the low side to me, but I have seen them run that low before.