Hi everyone,

I've tried for hours to find the correct cylinder compression for my
Mercruiser 3.0L -88, but I just can't seem to find it anywhere. I saw
similar engines rated at 130 PSI from the factory, but if anyone could
give me an authoritative answer on this particular engine, I would be
very grateful.

I just did a compression check on my engine, and get the following
results: 120, 120, 120, 180 PSI. I have little experience with this,
so I would appreciate any advice or comments on how to remedy this
situation.

Sincerely,

Carl, Sweden