250-500cc help any cr/wr250 2001-2005

hi ive been running in my rebuilt cr250 engine just taking it relativly easy but there is oil leaking from the small sprocket i removed the sproket to find that the seal was completely wrecked ????? when i built the engine i used new seals new sprocket new spacer and a new o ring any ideas guys???

As just a guess I have heard from others about oil from the FS: Is the chain too tight?

When you put the seal on did it go on ok or was it very tight? Maybe you were given the wrong part?

the chain was a little tight at first as it was brand new but quickly slackened off ??? maybe it was this

the seal was a nice snug fit pretty sure it was the correct one as the sizes were the same as stated in the parts list

still having problems with this again a new seal was fitted i took her for a spin for about 10 -15 mins and there is oil everywhere can anyone help?????????

Is the bearing on both ends of the shaft okay? Can you feel any play up, down,and side to side with seal removed? Do do have the internal o ring on the spacer? Does the bushing have grooves in it? How are you driving th seal in? Seal has to go int square. Are there any sharp edges on bushing when you push it in? Never overtighten your chain especially when its muddy, it puts a lot of stress on shaft. To me, think you are missing the o ring on the bushing/spacer that slides on shaft, between shaft and seal, or it is bad with grooves in it.

I agree with Darin on this problem. The o-ring is easy to miss or damage.

Thanks for replying ok here goes the o ring is there as is the spacer Yes there is play on the shaft when the seal and spacer is removed I was told this was normal?? Something is defiantly missing or wrong as the seal only lasts a couple of minutes): maybe I'll have to remove the engine and strip her down again