|
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. |
Originally Posted by F-2 Speedy
(Post 4631094)
what ignition, distributor, coil are you running
|
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. |
Originally Posted by nailit
(Post 4631134)
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. 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. |
Originally Posted by tnc110
(Post 4631114)
Daytona ignition. Not sure on coil.
|
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.
|
When it shuts off,it will not start right back up,right?you need to have a volt meter with you and probe the purple wire(its the run wire from the key swittch)
you'll have to work quickly. Good luck these problems such to find |
It will not start right back up.
I ordered another alternator. I'm hoping that it's just charging too much. |
15.5 volt if I remember correctly ?
where were you seeing this on the amp gauge ? if that correct its to high....should be around 12.8 - 13.2 ? could be over heating a component and failing till it cools off With the engine running / charging check the voltage at the battery ....see if the auto parts place can test it before you install it |
Yes on gauge. (Volt gauge actually)
|
so no start period ??? If that is the case
test the pick up coil in the distributor -- possible your issue if so buy the merc one -- read the post 502 will not start |
| All times are GMT -5. The time now is 06:39 AM. |
Copyright © 2026 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.