What could be causing gasoline to get into my oil?

Dear Car Talk

Dear Car Talk | Apr 01, 1996

Dear Tom and Ray:

I have gas in the oil of my 1979 Olds Cutlass. Is it possible that a bad distributor is causing this? -- Greg

RAY: Is it possible that space aliens were responsible for the Iran-Contra affair? Sure. But it's not very likely.

TOM: It's more likely that the carburetor is letting excess gasoline into the cylinders, and that some of that unburned gasoline is getting into the oil by flowing down the cylinder walls.

RAY: Although it's possible that a bad distributor could leave unburned gasoline in the cylinders -- by providing too weak a spark to burn all of the gas -- it's far more likely that the problem resides in the carburetor.

TOM: If you're lucky, it could be something simple like a misadjusted choke or faulty choke pull-off.

RAY: If you're not as lucky, it could be something inside the carburetor like a bad float, faulty jets or just OCCS (Old, Cruddy Carburetor Syndrome). Any of these problems would require a carburetor rebuild. And we'd suggest a factory-rebuilt carburetor.

TOM: And you shouldn't wait, Greg. Because of this problem, your engine has gasoline where it's supposed to have oil. And gasoline is a lousy lubricant. So unless you're trying to drive this car into the ground so you'll have an excuse to get another one, I'd get this fixed as soon as possible.

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