markw

Does anybody know anything about the OMC/Spitfire system? On my 91 Four Winns {350/260hp sbc} last year it would cut out after it got warmed up. This system has 4 coils and is crank triggered. I spent all last year changing parts on the fuel side because it cuts out when the secondarys open up.I took it to two shops both said they fixed it but it still happens.It will run all day fine untill about 3000rpm after it warms up then it cuts out.The boat runs under 170* and does not heat up. I don't want to waste another year working at this, need help.
thx MarkW

AZDominator

Sounds like that ECU is not advancing the spark. Check this by using a timing light while underway. I got to know the 454 OMC Spitfire system fairly well helping out my brother-in-law. Ultimately we ****-canned it for a complete MSD unit mainly because of the replacement/repair cost of the stock Spitfire piece.

Intolerant1

I also have a Spitfire. Cant help you with your problem but cutting out could be anything. I assume you already replaced the rotor, cap, and wires?

AZDominator

The other "easy" thing to try is to check your optic pick-up sensor located by the bell housing. This could have some corrosion or other build-up (oil/grease) that is confusing the signal as the engine revs above 3000. Do you still have the stock OMC fuel pump installed? Float levels in the carb adjusted? Just trying to help.

markw

I put a new carb on it replaced all the fuel lines. Took out the check vavle by passed the water sep. Put in a fuel press. gauge. The fuel presure is between 5-71/2 psi at the carb, but it still cuts out after it warms up at about 3000rpm.
This season I'm going to put a distributor in and by-pass the spit fire system and see if that takes care of the problem.
thx for the help AZDOMINATOR.
MARKW