Internal Hydraulic Leak

Sun Jan 18, 2004 6:41 pm

I have just bought a 1956 Cub, My Grandfather had one just like it. It runs fine, but the hydraulic pump leaks into the engine crankcase. Being new to the Cub family, I don't know if there is a gasket/seal that needs to be replaced or complete rebuild. Any information would be greatly appreciated. Happy Cubbing!!!

Sun Jan 18, 2004 6:49 pm

Mark, there has been a lot of discussion about this lately. There are o-rings in the hydraulic pump that are bad, allowing fluid to leak into the crankcase. The pump is an easy rebuild and should solve your problem

Mon Jan 19, 2004 5:44 pm

Try this link
There's not too much to the pump as you will see when you get it apart. If you replace all of the "O" rings this should solve your problem. Inspect the drive shaft to make sure it's smooth and not worn too bad. Mine had a nice groove worn into it where the "O" ring seals (or not) I had to clean it up by taking a few K's off the dia. then used a smaller "O" ring. It works fine now.

Good luck,