'95 omc cobra v-6 engine won't start

gbitting

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I have a Sunbird boat with a 4.3 liter v-6 omc cobra engine and volvo penta sx cobra outdrive. Have had trouble withengine since buying boat. Initially hard to start ok when engine warmed up. Later it developed a problem around 2500 rpm where it would surge and bog down. After playing with the throttle it would then take off and run. It would not idle below 1000 rpms smoothly. I rebuilt the carburator, replaced the spark plugs and wires, changed the fuel filter. Now the engine will start and immediately die out. I checked the fuel pump which appears to be good. low pressure pump produces about 4.5- 5 psi. Comprssion is good at 150 psi per cylinder. I had the carburator professionally rebuilt and flow tested. Spark plugs are black. I have not messed with the carburator jets as they were supposedly set thru the flow testing. Don't know where to go from here. Maybe someone can help me before I take it to the dealer. Boat has an omc cobra engine and vovo penta outdrive. Appears to have enlectronic ingnition.
Stumped ? Any suggestions would be welcome. Thank you in advance.:(
 

Bondo

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Re: '95 omc cobra v-6 engine won't start

Spark plugs are black.

Ayuh,... My WAGuess is, you Still have Carb issues...
 

gbitting

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Re: '95 omc cobra v-6 engine won't start

In the past I have messed with the carburator jets. It did not change the condition much. When it did run before the first carb was rebuilt the first time I could turn the jet screws all the way in and it still ran making me believe that I had a bad carb.There are 2 jets one for gas one for air. As this 2nd carb was supposedly bench tested for flow when i got it, I have not messed with the jets. How should the jets be set. How may turns out from being gently seated to at least try and get this thing running. Also I have set the idle on the carb as high as it will go to try and get it to start at a higher rmp as in the past this seems to have worked in the past. Any suggestions would be appreciated. I don't think it's ignition but I am unsure how to test this. I use starting fluid in the carb and it will start and run for a few seconds before dying out. I agree think it is carburation but the carb has be rebuilt by me and I also bought a differnet carb that again was rebuilt and supposedly tested. Appreciate the help, getting somewhat frustated.
Thank you again (will adjust jetstommorow could black plugs be from ignition timing ? something gone bad in electronic ignition ? )
 
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gbitting

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Re: '95 omc cobra v-6 engine won't start

I found out what was wrong. It was not the carburator. It was the kill switch that is up front by the ignition switch.;)
 
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