Rear main seal ?

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Rear main seal ?

Postby FritzTheCat » Tue Jun 16, 2015 11:55 am

Just bought my first Farmall Cub.It was in a garage for over a year and only started a few times. Now after running it for 20 minutes it started leaking a lot of oil out of what appears to be the rear main seal of the engine.I was told that this engine has some valves or something that gets pressurized if it sits to long without running and the main seal is probably ok. Anyone ever heard of this ?

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Re: Rear main seal ?

Postby staninlowerAL » Tue Jun 16, 2015 12:20 pm

Not the expert, but never heard that explanation. Usually the rear main seal fails from prolonged non-use of the engine, leading to splitting the tractor and replacing the rear main seal. Search for the topic. Forum member Tim (tst) offers a seal and carrier assembly that will fix the problem. Stan

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Re: Rear main seal ?

Postby John *.?-!.* cub owner » Tue Jun 16, 2015 1:06 pm

Rear main seals tend to loosen in the retainer with time. As mentioned, TST machines the retainer and installs a new seal (different OD). Oil sometimes accumulates in the torque tube and leaks out when you drive up and down a hill. The oil can come from the transmission, especially if overfull from water condensation. I suggest removing hand hole cover on bottom to verify if oil is coming from the front or rear. The crankcase is open to the air via the mesh in the filler cap, and I think the stuck valve theory is far fetched.
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