Fuel in oil!! HELP!!! PLEASE!!!

garykihara

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Jul 12, 2009
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Ok there is alot of fuel in the oil.....it started this morning...im assuming the mechanical fuel pump is leaking back into the block because there is alot of fuel....surely the carb cant dump that much fuel(2bbl)
 

Don S

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Re: Fuel in oil!! HELP!!! PLEASE!!!

Depends on what you have for an engine and a few other minor details. If you have a mechanical fuel pump, that would be the first place to look.
 

garykihara

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Jul 12, 2009
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Re: Fuel in oil!! HELP!!! PLEASE!!!

it is a 1997 merc. 5.7 2bbl alpha......i put the icm conversion kit on and it ran excellent.....10 to 15 minutes go by and then it slowly started to die. then it wouldnt idle and was hard to start. then it wouldnt start unless it was WOT and ran very rough would not idle. Then i noticed a fuel smell and the pcv tubes were spraying gas/oil mixture and checked oil it was very full and had alot of gas in it. im leaning towards the mechanical fuel pump leaching back into block but why would it be running that bad?
 

Lyle29464

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Mar 10, 2009
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Re: Fuel in oil!! HELP!!! PLEASE!!!

The gas went in the pan not the carb or the float stuck and you drowned it. But pump would be the first thing to look at.
 

spdracr39

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Aug 30, 2010
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Re: Fuel in oil!! HELP!!! PLEASE!!!

Almost certainly the fuel pump.
 

Don S

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Re: Fuel in oil!! HELP!!! PLEASE!!!

im leaning towards the mechanical fuel pump leaching back into block but why would it be running that bad?

lean real hard, because the fuel pump is the ONLY thing that can pump that much gas into the crankcase.

The reason it runs so bad, is the pump also has a clear hose on it that will pump fuel to the carb when the diaphragm fails. This would make it run very rich.

I would be wondering why this pump failed so suddenly and so bad. Fuel tank additives ????????
 
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