oil smells of gasoline

[Bud Man]

I just replaced my '89 Mercruiser 4.3L and when I started it up it ran rough and smelled of gas. Adjusted fuel mixture needle to specs, changed oil and started over. Still had gas problems with no power in the water and stalling. A mechanic thought the carb float might be stuck, since the intake manifold was off and turned upside down while replacing the engine. <br /><br />How do I fix this or could something else be the culprrit?<br /><br />Thanks for the help.

 

[boat doc]

Re: oil smells of gasoline

if you have a mechanical fuel pump, the diaphram probably has ruptured. Replace the fuel pump, and you should be good to go. should explain the runnig problem too

 

[flashback]

Re: oil smells of gasoline

Your post originally said " oil smells like gasoline" This tells me that you are getting raw gas into your crankcase, this is not good, 9 out of 10 times this is caused by a bad fuel pump..................check and make sure you have a "marine" fuel pump V.S. a automotive pump........the marine pumps have safe guards such as dual diaphrams and overflow hoses to keep this from happening..........goood luck. but we need to know what exactly you have

 

[Bud Man]

Re: oil smells of gasoline

Thanks for the help.<br /><br />More info: I have an electric fuel pump.

 

[boat doc]

Re: oil smells of gasoline

stumped..... One other thing I have seen is someone use an EFI fuel pump on a carb, and it pushes too much fuel past the needle and seat of the carb causing flooding. This type of flooding will usually cause hydrolock, and fuel will bleed past the rings into crank case.<br /><br />This is probably far fetched, but possible

 

[Bud Man]

Re: oil smells of gasoline

thanks guys,<br /><br />the fuel pump is a low pressure model given to me by the engine rebuilder, who put a cam for a efi engine which doesn't have the lobe for the mechanical fuel pump. It's actually kind of a funny story if it didn't cause me such grief.<br /><br />I am going to try freeing up the float, then rebuilding the carb if that doesn't work.

 

[boat doc]

Re: oil smells of gasoline

I would like to know what you find. I do know what you are saying about the cam lobe missing for electric fuel pump, no need to explain that one. Keep me posted. One thing though, if your floats are miss adjusted, then it will dump fuel, which you should be able to see when your fuel pump is running. If your pump is wired in direct ignition wire (usually purple), then your pump will not shut off, because the carb will not fill up with fuel. Usually mechs. wire fuel pumps into something that does not get 12 volts unless the engine is being turned over, or running though. Just something else to think about before doing that rebuild

 

[Bud Man]

Re: oil smells of gasoline

I have the fuel pump wired with the ignition switch, so it starts up before the motor turns over. The mechanic said the carb float should be able to hold back the pressure of pump since its low pressure.

 

[Bud Man]

Re: oil smells of gasoline

I have the fuel pump wired with the ignition switch, so it starts up before the motor turns over. The mechanic said the carb float should be able to hold back the pressure of pump since its low pressure.