2.3l omc died and won't start

MJTurner42

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Sep 13, 2017
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Hi all first time posting. I have a 1990 OMC Cobra 2.3 l engine. I was on the river and I heard the engine start to loose power and over the course of 30 seconds the engine ramped down and died. I could not get the boat started again. I have been playing with it in the yard and still cannot get it started. I have replaced the battery with a marine battery as the previous owner didn't know better. I have checked the fuel pump and am getting gas. I have replaced the fuel filter with a new one with new gas. I have unhooked the gas line from the onboard tank and connected it to a can of brand new gas. I have verified spark with a screw driver in all four spark plug wires.

I am at a loss for why it won't start.
 

alldodge

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When the throttle is pumped, do you see gas squirt down the carb?
 

alldodge

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Yes when I pump the throttle gas squirts into the carb.

Then if the gas is clean gas and not water then you have a spark issue. Pull the fuel filter and dump the contents into a baggie to see if there is anything but clean gas in it. When removing filter see if its completely full. Pull some plugs are see what they look like
 

MJTurner42

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I pulled the plugs. Cyclinder 1 plug was completely black with oil on threads. Cylinder 2 and 3 had oil on the spark plug threads. Cylinder 4 was clean.
 

Scott Danforth

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I would do a compression test if you found oil on the plugs
 

alldodge

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Those numbers tells me you need a rebuild or replacement, or at least head work
 

kenny nunez

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While the compression #s are off , did any water or any other fluid come out of the cylinders after the plugs were removed? There is enough compression for the engine to start.
Check the timing belt to be sure it did not jump a few teeth. There are timing marks on the sprockets that line up with marks on the engine.
 

MJTurner42

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When we checked the compression clear fluid came out of cylinder #4. My buddy said it was gas but it seemed like a lot. It flew about two feet into the air I'm wondering if it wasn't water....

We just replaced the timing belt yesterday. It was one tooth off and we fixed that.

Still no luck getting the engine to fire even after fixing the timing belt
 

alldodge

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Pull plug 4 again and see what's in it, then check for spark at all cylinders
 

kenny nunez

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It appears that you may have a leaking manifold. Once spark plugs are water fouled they are toast. Pull the manifold, flush out the engine and load the cylinders with oil and spin it over to keep rust from building up. Order a new manifold. Hopefully it is not a cylinder head or block problem.
 

MJTurner42

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Sep 13, 2017
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Just rebuilt the carb and that was a waste of time. Still no luck turning the motor over. I'm going to bring it to a shop. Any recommendations in CT?
 
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