Once Hot it will not stay running

[Lil Fesot]

I have a 87 OMC 2.3L with a Cobra outdrive. When I first put into the water, she runs great. After 10 min or so of running when I idle down to a stop it runs rough and stalls. It will start up but idle rough and stall. Placing in forward yields the same result, it continues to run rough and it stalls. For the first 10 minutes I can start and stop and it runs perfect. The rough running seems like how it runs when testing the ESA. Is is possible the ESA module is being effected by the heat and messing with my coil?

It was suggested that it might be a bad lower shift cable but if that was the case, why would it run so well initially.

I have also verified the interrupter and overstroke switches are functioning properly which again leads me to believe the ESA could be the culprit when it gets hot. I ran it on muffs for 20 minutes and it ran perfect, put it in the water and after 10 min of running, wala, it ran rough and stalled. Let it cool, its good to go until it gets hot.

Your help is greatly appreciated.

 

[Lil Fesot]

Re: Once Hot it will not stay running

Quick Update. Ran on muffs in the driveway for 45 minutes, runs perfect. I decided to double check the timing and the dwell. When connecting the dwell meter, when I connected to the coil it began to run real rough, exactly like the problem I have been having on the water.

Not sure what it means but additional information. I could really use some input on what to try, check or detonate.

Happy 4th!!

 

[breastman569]

Re: Once Hot it will not stay running

Im having the same problem with my 305 i/o it will run great for a couple of hours but when i stop and just float around the lake or im waiting for another wakeboarder to suit up it will then become hard to start and when it does it will idel really rough but as soon as i drop into drive or put it under load it will die. we had this same probelm ten years ago and thats why we parked it, so we rebuilt the card and the distributor and the problem seem to go away untill last weekend for it second but much longer trip. anyway the more and more we thought about it we traced it back to the coil. we think its the coil because ours is encased in oil and as long as we are moving and pumping cold water through the engine it is staying cool enough in the engine hatch, but as soon as we stop and it heats up in there it acts up.

when this happens i would have buddy manualy run the throttle up over normal rpm's as i drop it into gear and get it moving and when it finally cools down in the hatch it runs fine.

that being said we have a new coil that we and putting but have not tried it yet, were shooting for wednesday. hope this helps.

 

[Lil Fesot]

Re: Once Hot it will not stay running

Another update.

Thought it might be the coil but in talking with a buddy of mine, he suggested I change out the condenser. I keep a spare and put it on. I could connect my dwell meter with out the engine wanting to stall.

Put it in the water and ran 10 min upstream and then back to the launch. She idled fine and went into forward fine. Ran it another 15 min (at 3500 - 4000 rpm) upstream and back again. Everything appears to be good. I planned on taking her out yesterday but never made it. Plan to do it again today and run much longer than 25 min. I feel pretty optimistic. At least for the time being I do not beleive it was the lower shift cable or any of the ESA components.

Safe Boating!!