I have twin 225 HP optimax, I checked compression...one side has 80,80,80,80,90,90 and other side 90, 90, 90, 90,95,90. So those are little bit low? Need rebuilt powerhead?
I know nothing about your engine but similarities surely exist: The serv man for my 90 hp triple, looper, says cylinders should be within 10% primarily. It goes on to say that generally speaking readings below 120 could be cause for concern. They don't set a fixed number due to deposits in the cylinders and all which could give an erroneous reading. My current engine is running 115 and are within a couple of # of one another. It runs out fine.
You checked your compression for a reason and maybe yours is in need of overhaul. Loading up the cylinder walls with oil and retesting can give you an idea immediately as to where you stand on compression.
The manual states 110-130 psi for that year model. If both are running fine I would do a powertune or deep creep cylinder soak overnite to free up rings if sticky and start running Quickleen in your fuel.Also recheck with a different gauge as the one used may read low....
