Hey if anyone can give me some imput it would be helpful. Heres the situation. I have a 1985 Scarab 3. with Twin 454 HO 370 HP. I had an over rev situation when one of my drives blew. I shut it down fast, Much money later with new drives i now have a new problem. My left engine is only runing on 3 cyclinders. People are telling all kind of things. Like i have bent valves, droped my valve seats, or even just blew my head gaskets. I lost 3 on one side and 2 on the other. It pops back threw the carb. When engine is cold i can get up to plain but when engine is warmed up no power when under load. Any ideas.

Also anyone know how i can find the specs for the engines on this boat ?

I would do a compression test before I did anything else. That will at least give you a idea what the problem is. It could be something stupid like a loose rocker arm- but a compression test will give you a place to start. I think I might have the specs at home on those engines- I will check.

Good luck-

Scott

Second the leak down test.... I hate to ask... but have you checked your distrbutor? Sounds like timming is way off... maybe rotor is out of place and you are missing.

Could the timing chain have jumped a tooth?

Sounds Like Bad Rings

Thanks guys for your imput. I have found the problem i took the heads off and i have sunken seats and broken valves. Heads are trash. Now i need new or some used heads