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Ignition shutting down when WOT.

This has happened a few times. When ruining wot for 30 seconds or more the boat just shuts down. . like all power is killed to the ignition. It sits for a minute or so then everything comes back to life. Seems like there is a breaker tripping and then automatically resetting. Are there Auto resetting Breakers somewhere? This is a MerCruiser originally had a 454 now as a 540.

what ignition, distributor, coil are you running

You could also be running it out of fuel. What is your set up?

Had a similar issue years back. Dist cap and rotor had some corrosion and under heavy load engine would just shut down.
It also could be coil or a distributor module that is heating up.

Quote:

Originally Posted by F-2 Speedy (Post 4631094)

what ignition, distributor, coil are you running

Daytona ignition. Not sure on coil.

I had a similar issue.. was clueless as to why!! While running, I lost rpms and fell on its face. Was still running when I stopped, I gave it throttle and it was fine. Did the same thing a few times. 454 mag mpi... btw.

I ended up finding a thread where Mark Boos mentioned it was the TPS.. that was it.. fixed it. Throttle position sensor. oh, I wasn’t WOT, but just throwing it out there.

Quote:

Originally Posted by nailit (Post 4631134)

A scan tool hooked up while running would have pin pointed right away --- TPS parameters.for your app ^^^^

for the OP it was never mentioned if this was a carb or MPI engine. IMO this is a carb app. More info is needed. Huge difference from carb to MPI engine for shut down issues.

to the OP - what does voltage show at shut down ? voltage on the gauge - voltage across sections of the engine with a volt meter - at the starter and at the alternator - what is voltage readings ??? Is the alternator going bad ???

Next test --- sealed inline spark checkers - do you have spark trying to recrank the engine ? you can even put a sealed spark checker inline for the coil to top of distrib cap - do you have spark ?

Next is it the fuel side - what is your fuel pressure at engine shut down and at trying to restart ?

3 tools here will find your issue(s) or at least where the problem lies.

Quote:

Originally Posted by tnc110 (Post 4631114)

Daytona ignition. Not sure on coil.

when it happens you need to not turn off the key, open the hatch and see if the red status led is flashing fast.

This is a carb engine. Voltage seems higher than it was before issue started. 15.5 volt if I remember correctly . After the first time it happened I replaced both batteries and the alternator and the problem is still present. It runs great no signs of missing or sputtering it just cuts out 100% when the issue occurs. It seems to me as though something is tripping and then resetting itself when given enough time.

I chased a problem like this some years ago..........it turned out to be the ignition switch of all things, would only do it at WOT go figure.