67 ford f100 oil in fuel filter. And not running unless gas is poured in carb


Asked by Dec 30, 2012 at 06:52 PM about the 1967 Ford F-100

Question type: Maintenance & Repair

6 Answers


Assuming you still have the OEM style mechanical fuel pump. I'd say the rubber diaphragm inside the pump has split allowing oil, from the crankcase, to be sucked in with the fuel. HTH. -Jim

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Best Answer Mark helpful

I do have the oem style. Could this cause truck to not running? Thanks jim This is the most help i have gotten so far.

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You're welcome. Yes it can prevent it from running. That diaphragm creates the pumping action which supplies fuel to the carberuator. To test the fuel pump, disconnect the fuel line at the carb. Get a metal or glass cup or jar. Hold the disconnected fuel line in the container while a helper cranks the engine. Gas should shoot out in bursts as the engine is cranked. I'm betting you get little or no fuel. Then go ahead & replace the fuel pump. Change your oil too as fuel may have leaked into the crankcase as well. HTH. -Jim


Will keep u posted thanks again. Im sure i will have alot of questions


You have oil in the filter because there is a tube going to the valve cover. That's the positive crankcase ventilation for the engine. The fumes come up and condense leaving the oily residue. The 67 Fords have a carburetor and sometimes the fuel in the bowl leaks down into the intake when parked. It takes a bunch of cranks to refill the bowl before it fires. Check out the pump as mentioned and add a clear/translucent fuel filter up stream so you can see what's going on in the future. I had a 79 Jeep like that. I ran a piece of aquarium tubing into the cabin and would squirt a little starting fluid into the carb to reduce the drain on the battery. It would fire, spin the engine enough to pump the fuel into the bowl. Just needed when the truck sat a few days.

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Ok Mike, you're welcome. Happy to help. -Jim

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