In need of some help!

Just replaced the outer seal on a 2005 yz450f water pump because it was leaking, changed the seal started it for about 15 seconds & it didn't leak, then proceeded to take it up & down the street a few times & when I went to park it I realized it was leaking fairly steadily....& then I let the bike cool for a few mns and then I let it idle for probably 30 seconds & it wasn't leaking but I can't run the bike anymore cuz my yoshimura exhaust is too damn loud & it's getting late & now I'm like wtf.. & no the seal is NOT in backwards & my shaft is not grooved. So here's my question, does a new seal need to "set in"? Or do I have another issue?!?

^^just really paranoid something's wrong

I'd say get another seal and do it again and if it does then something is really wrong

Did you inspect the shaft for wear? 

The seal can only seal if the shaft is perfect.

Did you inspect the shaft for wear?

The seal can only seal if the shaft is perfect.

there's marks all over where the old seal was but I can't really feel anything?

One thing to look at is the balancer shaft bearing.  The inner end of the shaft is supported by the balancer shaft.  With the right side cover off, check for vertical play in excess of .006".

 

Your seals are oriented as shown here? 

 

SealsLabeledsm.jpg

One thing to look at is the balancer shaft bearing. The inner end of the shaft is supported by the balancer shaft. With the right side cover off, check for vertical play in excess of .006".

Your seals are oriented as shown here?

SealsLabeledsm.jpg

not really sure how to check but I guess I'll just wiggle it around and see if there's play? & it doesn't leak right away, it takes a good 30 seconds of idle and a slow drip will start. & if the balancer bearing is shot is that easy to replace? But I think it very might well be just the shaft, I could see marks all over where the old seal was but I didn't really see any scoring, I should probably feel it to make sure it's smooth. & how sensitive are these shafts to leaks?

The shafts are really fussy.  Roughness and scoring in the sense you probably think of either one are well beyond what it takes to get one to leak.  Anything you can feel by dragging a fingernail over the surface is probably enough to cause trouble.  Looked at another way, if you can't polish the marks off in a few minutes with 320 grit, it's bad.

 

The balancer shaft bearings in the '03-'05 Gen1 450's require the cases to be split to replace them.  The Gen2 ('06-'09) can be done in the bike, but it's a challenging procedure, and not for the marginally skilled.  The link below may also work for the later Gen3 & 4 engines, but I haven't researched that.

 

http://www.thumpertalk.com/topic/1059507-07-wr450-help/?tru=GKvpN#entry11302329

The shafts are really fussy. Roughness and scoring in the sense you probably think of either one are well beyond what it takes to get one to leak. Anything you can feel by dragging a fingernail over the surface is probably enough to cause trouble. Looked at another way, if you can't polish the marks off in a few minutes with 320 grit, it's bad.

The balancer shaft bearings in the '03-'05 Gen1 450's require the cases to be split to replace them. The Gen2 ('06-'09) can be done in the bike, but it's a challenging procedure, and not for the marginally skilled. The link below may also work for the later Gen3 & 4 engines, but I haven't researched that.

http://www.thumpertalk.com/topic/1059507-07-wr450-help/?tru=GKvpN#entry11302329

I really appreciate the help man, & I can actually feel 2 distinct notches where my finger nail gets caught now that you told me that, I didn't know the shafts had to be that spot on?? But hey I guess it's a good thing I bought extra case gaskets I'll update this when I get the shaft.

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