Questions and Answers

F-250 Has Gas In The Oil Q. 1989 Ford F-250 unknown mileage. The truck was running okay and then died one day. It will turn over but has not started since. The only thing the mechanic checked was the oil. He said it smelled like gas so we would need a new engine. Any opinions on this?

A. Before I condemn the engine, I would change the oil and filter first. I'm willing to bet once you do that it will start and run. What happens is the gas washes the oil off the cylinder walls and that lowers engine compression enough to kill the engine and keep it from starting.

Now, how did the gas get into the oil?

You didn't mention engine, but I'm willing to bet you have a Ford V-8 with an engine mounted fuel pump. The diaphragms in these pumps go bad and develops holes and cracks. Gas passes through these holes and cracks right into the oil pan.

So change the oil and when it starts, change the fuel pump.

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