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Oil seal. Which way?

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Had to do a bottom end rebuild on my 2007 WR450 and am replacing all oil seals while I'm at it. I took pictures of all except one and I can't remember which way it goes and there's no mention of this seal in the Yamaha manual. Its in the right side crank case cover that also has the water pump assembly. Its the one the very end of the crank shaft slides into. It goes seal, washer, snap ring. I looked at several you tube videos and none mention anything about oil seals and no pics that you can tell anything from. Please help !!

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The "closed" side of the seal faces in toward the bottom of the seal pocket, and the lips of the seal face toward the crank. The lips face out to you as you install the seal.

Since the oil this is supposed to seal is inside the cover, this will seem backward if you start to think about it.  Once you understand what's going on, you will think, "The oil will blow down the seal lips and leak right past the seal", and you would be correct.

The thing is that it's supposed to do that in this case, for a couple of reasons: The first is that the seal serves as a sort of pressure regulator.  Once the pressure from the pump gets high enough, the excess pushes past the seal lips and limits the pump's output pressure.  The second is that by doing this, the oil that leaks past serves as an "oil bearing" for the seal itself, which would be unlikely to survive for very long at the very high RPM that the crank spins.  You may notice that there is no wear mark on the crank where this particular seal runs on the crank as there almost always is on the water pump shaft, for example. 

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What I was concerned with was since there is a passageway into the oil filter I didn't know if it was to keep the oil from blowing by into the filter compartment  or to keep it from blowing from the filter side into the crankcase. Confusing!!  Thank you for your help. Wont be long now!

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