Re: Compression Spec on 1993 Evinrude 150HP
Just got a PM questioning if big V6s "should" read 80-90psi.
There is no "should". There are too many variables. One engine, measured by three different people with different guages and under different conditions will give readings varying by as much as 20-30psi.
The only real value of compression testing multi-cylinder 2 stroke outboards is to identify single cylinder or adjacent pair failures. All 3, or 4, or 6 cylinders simply do not go bad by the same amount at the same time.