OMC Cobra wouldn't start

[pra51]

I have a omc cobra 1991 4.3 lit.with holley 4 barrell card.First time out this season,it started fine ran wot fine cruised lake for a hour no misses or anything.We stopped,droped anchor for a couple hours,then it wouldn't start.<br />Cranked fine,just wounldn't fire.I first looked in carb to see if was pumping gas,it was,good spray.Checked choke,it was open and not binding.Still wouldn't start.The 2 switches monted on side of shift cable,side by side,one above and one below,I pushed in on the bottom one,small push button.I believe this is the ignition interrupt switch,and at the same time I also unscrewed the fuel water seperater filter part ways to see if fuel in it.Tried starting ,it started,thankful beings battery was getting run down.Question is any ideas on problem?Did these final things have nothing to do with it finally starting?I sure don't want to go through that again!

 

[BigBabyLou]

Re: OMC Cobra wouldn't start

I've been having the same problem: cold starts are perfect, always at the first crank. However, starting warm is pretty bad, I am afraid I would run down the batteries.<br />I have Holley 4bbl carb with electric choke. No matter what I set the choke to, it always starts hard when warm.<br /><br />Can somebody help us? Thanks!<br />Lou

 

[mvaughn]

Re: OMC Cobra wouldn't start

Are you guy's pumping the throttle when trying to start?

 

[pra51]

Re: OMC Cobra wouldn't start

I did try that,pumping it when this happened..Mine only did that one time,although I didn't stop again and try it.Was afraid It would do it again.I really think mine is in the switch,interrupter switch that is.Mine was as if the ignition had been disconnected.

 

[mvaughn]

Re: OMC Cobra wouldn't start

Phil, <br />I would run it in the driveway, with muffs, See if you can get it to do it again, try to see if it is in fact the switch, could have stuck?

 

[Boatin Bob]

Re: OMC Cobra wouldn't start

I don't think it would be the ESA switch because that should only stumble the engine unlike the Merc which can actually stall the engine. But it could be something temperature related, maybe the coil or points if you still have them?

 

[RonB1954]

Re: OMC Cobra wouldn't start

I have a similar engine and this happened to me a few times before we discovered that the 2 main fuses <50 amp> that are mounted on or near the engine in the rubber jackets were not making good contact. This also had my electronics messed up off and on.<br />We cleaned these and replaced the fuses and no more trouble!<br />Good Luck<br />Ron

 

[BigBabyLou]

Re: OMC Cobra wouldn't start

My problem is definitely not electrical, I'm positive on that. I used to have a bad contact at the main 50A fuse but that's in the past now. Shift interrupt switch and ESA are working properly, I am getting a good spark. Looks like my carb is to blame. I bought it as a rebuild and I've had warm start problems since.<br /><br />No, I don't pump the throttle, I don't want to flood it. I just open the throttle maybe 25% or more and try to start. Takes long time to get her at least sputtering, coughing and sneezing and then she finally starts.<br /><br />Lou

 

[akriverrat]

Re: OMC Cobra wouldn't start

phil, next time pull plugs and see if you have any water in cylinders.