Re: 1985 evinrude 9.9 ignition problem

[Don]

OK, so this is NOT the engine you were asking about cooling performance…
Like others have said, let’s not skip the basics so we can avoid confusion…
Well, the compression seems good…
You say it runs and idles great, but didn’t seem responsive….Seems like a bit of a contradiction….
You report no drop in RPM when pulling one of the plug wires, which would indicate a dead cylinder….You say the spark jumps your tester great, am assuming this is while cranking, not while running, is this assumption correct?
Do you have one of the peak reading voltmeters, so you can do running output tests?
If not, you could try those inline spark neon testers or a timing light to monitor spark while the engine is running. There may in fact be one dead cylinder, but the problem might not be spark related…I am assuming you have replaced the plugs, try different ones even if the plugs are new…Just because the plugs are new, doesn’t mean they (one of them) isn’t defective….
I just don’t want to lead you down the wrong path….Don