Gasoline in the crankcase? Check the carburetor float and your fuel pump first.

Dear Car Talk

Dear Car Talk | Dec 01, 1996

Dear Tom and Ray:

Recently, I restored a 1974 Triumph TR-6. I installed new valves, new
rings, new bearings and seals. Twice since then, I have found the fuel
running out the rear seal. And upon draining the crankcase, I have found
that it was full of gasoline! I rebuilt the carburetors and the engine runs
fine, but I cannot figure out how fuel is getting from the gas tank to the
engine crankcase. If the carburetor valves were leaking, I would think the
engine would run rich or stall from flooding. It does not. Any other ideas?
-- Harold

RAY: Gee, Harold. How interesting. If you have a TR-6 that's actually
producing gasoline, you might want to call OPEC. I'll bet they'd be willing
to give your driveway "member country" status.

TOM: Actually, I have two ideas, Harold. One possibility is that the
carburetor floats themselves -- not the valves -- need replacing. The
floats may be porous, and may be slightly submerged. Not enough to make the
car stall, but enough to let excess gasoline flow into the cylinders and
down into the crankcase.

RAY: The other possibility is the fuel pump. The '74 TR-6 has a mechanical
fuel pump, and if the fuel pump is bad, the diaphragm in the pump could be
leaking fuel right into the crankcase. And that would fill it up in a

TOM: So here's what I'd do. I'd start by replacing the fuel pump. If that
doesn't solve the problem, I'd replace the carburetor floats next. Then, if
you're still creating gasoline after that, I'd call Sheik Yerbouti and ask
him to send you an OPEC application form.

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