Hi sadly my force 70hp blew up on sunday and was towed in by the coastguard. Looking at a 50hp mariner as a replacement. Does anyone know what the compression should be on each cylinder?
Measured psi varies too much with gauges and technique to quote psi.
If you do the compression test EXACTLY as described in the Engine FAQs with a good gauge, you should get both cylinders within 10% of each other and over about 100psi. The 10% is the important part.
