Gas is getting into the oil pan.

Dear Car Talk

Dear Car Talk | Jul 01, 1998

Dear Tom and Ray:

I have been working on a feed truck for some time. The gas is getting into
the oil pan. I put on a new carburetor and that didn't stop it. I put on a
new fuel pump and that didn't stop it. I put on another new fuel pump and
that still didn't stop it. Can you help me? -- Ted

TOM: A feed truck? That's one of those little catering trucks that sells
donuts and coffee at construction sites, right? We call them "roach

RAY: I think he's talking about a farm vehicle. Anyway, Ted, here's what
I'd check. I'd start by making sure the thermostat is closing.

TOM: Right. If the thermostat is always open, the engine will never reach
proper operating temperature. And at less-than-proper-operating
temperature, the fuel doesn't combust completely, and the leftover fuel
would find its way past the rings and into the oil pan.

RAY: Another possibility is that your choke is never opening up. That would
cause the carburetor to continually pour way too much gasoline into the
cylinders, with the same result.

TOM: And one other possibility is that the carburetor you put in is no
good. You say you replaced the carburetor, but you didn't say with what.
Did you put in a new carburetor? A rebuilt carburetor? Or just the
carburetor from your neighbor's feed truck? Carburetors are touchy. So if
all else fails, you might want to try swapping another carburetor in there
and seeing if that fixes it. Good luck, Ted

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