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Oil in fuel tank

Oil in fuel tank

Oil in fuel tank

Does any have any experience with the possible causes of oil in the fuel tank (caterpillar engine 3126.) or any tests to pinpoint the problem.

RE: Oil in fuel tank

Obvioulsy there are some mechanical ways it could get there - although I don't know enough about that design to figure that out BUT

Maybe somebody put it there -- vandalism??

RE: Oil in fuel tank

New one to me.
Is there by chance a fuel pre-heater that uses the warm engine oil?
Look at where and how the fuel filter base mounts to the engine. Any oil passages in the block close to this area?
Have you called your CAT dealer? Try to figure out a way to have a conversation with an actual mechanic. Be creative.

RE: Oil in fuel tank

I don't know about your particular engine,but it happens a lot with the Mitsubishi 40M0 engine.It's caused by the input shaft seal leaking - the lift pump is at the front of the rotary injector pump,and instead of diesel leaking into the sump,it pulls engine oil into the pump....then back to the tank by the return hose.

RE: Oil in fuel tank

I'm with Lada on this, but if you have enough oil in the fuel tank to be able to detect it and it is pulled in through the pump, shouldn't you have been having an oil comsumption problem as well?


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