OMC engine stalls when accelerating

[whitesig]

OMC V8 235 HP, 1978<br /><br />The engine stalls/stops suddenly when accelerating. It runs fine at idle. I placed the engine in neutral and increased the trottle and it ran fine. <br /><br />I've also noticed that if I use the trim while the engine is running the engine will stop rather quickly.<br /><br />Do I have two problems or are they related?

 

[metwrench]

Re: OMC engine stalls when accelerating

Gary, check the post " OMC wont go over 3000RPM" In this post we go through lots of Diagnostic tips that may relate to your Problem. There is many things that can cause your Condition, When was the engine serviced last ? Fuel Filters, Plugs, Points , Ignition system ??? You mosy Likely have a failure of either Ignition or Fuel. Did this suddenly come on ? Slowly happen ? Explain ?

 

[whitesig]

Re: OMC engine stalls when accelerating

I printed off the post " OMC won't go over 3000 RPM and will try some of them on Monday. I changed the plugs and points last season. I changed the points from the ones that open and close manually to the magnet type. I changed the canister fuel filter this season. I thought this might be the problem. I read in the post that there may be another fuel filter in the carburator.<br /><br />The boat ran great last year when I put it up for the winter. The first time I took it out this year it idled fine and accelerated but never reached top speed. The next time I took it out is when it wouldn't accelerate past idle speed. I took it out yesterday but had the same problem.<br /><br />I've noticed quite a bit of corrosion on the relays for the power trim and tilt. I am going to clean them up on Monday. When I engage the power trip the motor stops abruptly. I have a couple spare relays I will swap out.<br /><br />Last year I also replaced the power control unit switch. Since I've done this the forward control seems stiff.<br /><br />Thanks, Gary

 

[Liquid_force]

Re: OMC engine stalls when accelerating

I'm a long way from an expert - but that sounds exactly like what one of the techs. at my local dealership described as a faulty accelerator pump.

 

[liquidasset]

Re: OMC engine stalls when accelerating

Try rebuilding the carb. If you have a Rochester 4bbl the kit is 18$ at autozone. I had this problem and that fixed it.