OMC 2.3 Cobra won't start

lisieux14

Cadet
Joined
Aug 13, 2019
Messages
22
Hi all

I recently bought a bowrider with a 1988 Cobra OMC 2.3 fitted and it was running fine having been recently serviced.
Problem is now i can't get it to start.
It turns over and tries to start and if i crank the throttle it starts for a few secs and then just dies.
Anyone any ideas as its doing my head in.
I don;t have much boat engine experience but a bit of car engine knowledge but i'm stumped.

Thanks
 

Scott Danforth

Grumpy old guy who plays with boats
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Jul 23, 2011
Messages
33,377
welcome aboard.

first, how are you starting it.... what steps are you going thru exactly.

list them.
 

lisieux14

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Aug 13, 2019
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Hi. Thanks. Starting to wonder if i made a mistake :)
With regards to starting, full tank of fresh fuel, fresh charged battery, muffs on the cooling fins, engine recently serviced and it will turn over fine and start for 3 or 4 secs before a fuel starve and then just keep turning until the battery dies. I have to keep the key in the start position though for the 3 or 4 secs it runs. i leave it go, it dies straight away
 

kpg7121

Petty Officer 2nd Class
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Aug 25, 2018
Messages
174
Those carbed engines can be finicky on a cold start. Pump the throttle 3-4 times & see what it does. It sounds like you're either flooding it or not giving it enough gas. You have to find the sweet spot, so to speak. Also, I would pull the plugs & see if they're wet with gas. If so, it's flooded. You need to dry the plugs because that engine will never start if the plugs are wet.
 

lisieux14

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Aug 13, 2019
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Right so i took off the lift pump.out it back together and it started,ran for 10 secs and died.wont start again now.sounds like flooding.how do i fix this?
 

lisieux14

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Aug 13, 2019
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Took the plugs out, very sooty for new plugs,cleaned them up and it ran again for a few secs and died.gettin fuel to the carb cos it sprayed across the boat when i disconnected it and cranked it.is there a way to turn down the fuel mix or does the carb need to come out
 

kpg7121

Petty Officer 2nd Class
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Aug 25, 2018
Messages
174
If it's flooding out could be time for a carb rebuild. Could be the float is stuck. Try tapping on the front of the carb where the fuel line is. That may break it loose but it's only a temporary fix at best. Btw, is the choke plate open or closed?
 

lisieux14

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Aug 13, 2019
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The plate at the top is it? The flap is closed on start and opens with the throttle.heres the thing though the olugs were dry when i took them out.should they be wet if flooded?is it a carb off to check the float?
 

kpg7121

Petty Officer 2nd Class
Joined
Aug 25, 2018
Messages
174
The plate at the top is it? The flap is closed on start and opens with the throttle.heres the thing though the olugs were dry when i took them out.should they be wet if flooded?is it a carb off to check the float?
Black soot on the plugs means it's running rich. Has the carb ever been rebuilt? What service was done on it?
 

lisieux14

Cadet
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Aug 13, 2019
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Oils,water pump,filters and plugs. Carb doesnt look like it was touched in a while
 
Last edited:

Lou C

Admiral
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Nov 10, 2002
Messages
6,800
You might have a sticking float or bad needle valve that is not shutting off fuel flow as it should when the fuel bowl is full (just like a toilet valve!) The choke valve (top flap) needs to close on a cold engine, but as soon as it starts, it should pull open a fraction of an inch to give the engine enough air to keep running.

Cold starting....
Pull out throttle control to disengage shift system....pump throttle fully open 2x to allow choke to close and accel pump to squit fuel in to venturi...then set throttle control about 1/3 advanced...then crank it till it starts...it NEEDS the throttle to be open to have the fast idle needed to keep running. If you are not doing this it will never keep running with a cold engine.
 

lisieux14

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Aug 13, 2019
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Thanks for that lou.i have an old morse throttle lever and cant seem to run on just throttle out of gear.cant find a button or lever to disengage the gears
 

TwoBallScrewBall

Lieutenant Commander
Joined
Sep 14, 2003
Messages
1,695
Check the ESA bracket and make sure that the roller tip is sitting in the middle of the "V" notch. If the ESA is triggered, it will run like crap and seem very rich.

Also, you said that it will stay running when you have the key turned then stop when you let go? If that is the case, these are set up to provide direct 12v to the ignition when starting, then when you let go of that key the 12v turns off and a lower voltage is sent to the coil through a separate wire. You might have a problem with this wire.

Also check the carb for dripping gas after it has just stalled. If it's dripping. you have to adjust the carb float/needle height, or may need to replace.
 

Scott Danforth

Grumpy old guy who plays with boats
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Jul 23, 2011
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33,377
you pull the handle out toward you like Lou told you to do. grab the base and pull outward about 1/4". that is how OMC sourced controls work
 

lisieux14

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Aug 13, 2019
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brilliant. thanks all. if thats the cause i will actually do backflips around the garden. its been sitting on my drive for over a week and ive a mooring paid for it already that im 2 weeks in to :(
 

Lou C

Admiral
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Nov 10, 2002
Messages
6,800
Hope that works out for you. Keep in mind that these engines were a variant of the Ford OHC engines like those used in European Fords and US Fords back in the '70s, '80s and '90s. They come with points and condenser distributors (old school) and a Rochester 2bbl carb if I remember right on the 2.3 liter, not a Holley. As such the are basic and simple but its old school car tech which most younger folks are not familiar with. My cousin had a Ford Capri circa 1971 (sold as a Mercury in the US) with the Ford OHC 2000 cc engine, the 2.3 is a bigger version of that design....
 

lisieux14

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Aug 13, 2019
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Well.unfortunately that hasnt done the trick.put new leads on it.gave it the 2 pumps and start with 1,3 throttle and just still turnin over 😭
 

lisieux14

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Aug 13, 2019
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This is what im working with. When i left the choke flap its not soaked in petrol at all
 

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lisieux14

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Aug 13, 2019
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Ok if i unplug the esa cables its starts better but still dies and fuel pisses into the carb after the stall.if i try with the esa in it wont turn over and i get no fuel under the choke flap.when it starts and i give it throttle it dies straight away.when i start it (esa unplug)with 1,3 throttle it struggles and wont turn over and when i have no throttle it starts and then 5secs later dies. Im really confused
 
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