Countershaft Seal

So I did my first bottom end rebuild on my YZ250 and everything went great (new crank, crank bearings, and crank seals). Since I had it apart I put in a new piston as well since I had 21 hours on my previous piston. The bike fired up on the second kick, and saw no leaks between the cases, etc.

I rode it up and down my street a few times to check that everything worked smoothly. When I got back I looked for leaks again and saw oil pouring out of the countershaft seal. I had replaced this seal as good measure, so obviously I did not install it correctly. I applied grease around the outside of the seal and pressed it in with my fingers and used a socket to lightly tap around its perimeter to seat the seal into the case.

Do I need to press the seal in further? It is flush with the outer case and that's how the old one was, but do I really need to pound this new one in? Any suggestions? Or do I just go ahead and buy a new seal?

Put another one in, dry this time, and check to see if your transmission vent is kinked or clogged. Generally, flush is correct. I never lube them up, I want them to grip the case. The sealing lips get moly grease.

Isnt there a seal inside the case too.....an oring under the bearing under the sprocket bushing deal.

Look at the parts lists: there is often an O'ring inboard of the collar that the seals goes against, the one that the sprocket fits against.

All of the parts diagrams I see only show the seal, then sprocket, then lock tab, then nut.

Would you guys mind showing me a diagram of what you are referring to? Thanks.

The bike is a 2005 YZ250

that o ring is there on all of them.

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