Drive oil leak

[Valkorado]

As if the development of the summer monsoon wasn't bumming me out enough, this morning I noticed a few drops of oil behind the engine but in front of the rear tire. Got down on my back to see that there is a drip coming from around the rubber boot that covers the U-joint.  We had to fight getting the shaft back in when we serviced the splines this spring.  Is the most likely culprit a trashed o-ring?  Any suggestions appreciated.  Looks like I'm grounded until I can get it fixed.    

[hubcapsc]

Better pull it apart again to see what's up, hopefully not much.
It should be dry and clean inside the swingarm, hopefully
you'll see where the goo is coming from...

The last few times, I've raised my swingarm till it was level, maybe even
the rear was higher than the pivot point... anywho... the shaft seems
to go on easy when the swingarm is raised...

-Mike

[Chrisj CMA]

trashed O-Ring?  What O-Ring would you be referring to?  I would think the struggle you refer to is getting the drive shaft back into the u-joint.  There is no O-Ring to "trash" there.

Now if oil is leaking at the u-joint boot, it could be the output shaft oil seal.  This is not unheard of.  And its not really the end of the world.  Its changeable by yourself without taking the motor out.

You do have to remove the drive train and u-joint and boot and a few parts to get down to that seal, but it can be teased out and a new one pressed in....search the old archives, there are pictures

[Joe Hummer]

My guess would be it is your pinion cup seal that has failed and you are seeing final drive oil that has made its way up the axle tube.  When mine had gone (and had to replace the pinion cup), I found oil all the way up the axle tube (with mostly dry crusty stuff at the u-joint). As Jeff said, you will need to remove the rear tire and final drive to get to the u-joint so you will probably discover what is causing the problem eventually.  Whatever you do, I would get a replacement boot because if it is dripping oil out...it could let water in. 

Joe

[Jess from VA]

I might just clean it all up and go for another (short) ride before assuming it is internal.  Couldn't you have just ridden thru some gunk that splashed up there and is dripping back off?

Could your dragon drool tube have filled completely and upchucked?

You could certainly pull the side cover and a few things out of the way and pull the dreaded boot back (from the trans side, not the swingarm side), and look inside to see if you have oil in there?

http://www.rattlebars.com/mtz/ujoint.html

[Valkorado]

Thanks for the replies.  Now I'm getting depressed.

For the record, I'm not even a novice mechanic and don't have a garage but I am trying to learn what I can.  Jess, it really looks like it's coming from inside of the boot.  I was just wondering if it could be that my buddy and I botched something when servicing the splines, as it was our first attempt.  I've ridden the bike at least a couple thousand miles since with no problems, but I'm afraid to ride it now.  You guys think it's safe to ride 65 miles to a friend's garage?

[sandy]

Thanks for the replies.  Now I'm getting depressed.

For the record, I'm not even a novice mechanic and don't have a garage but I am trying to learn what I can.  Jess, it really looks like it's coming from inside of the boot.  I was just wondering if it could be that my buddy and I botched something when servicing the splines, as it was our first attempt.  I've ridden the bike at least a couple thousand miles since with no problems, but I'm afraid to ride it now.  You guys think it's safe to ride 65 miles to a friend's garage?

Check engine oil and drive oil level, then go ahead and ride it. 65 miles is not a problem.

[salty1]

Check the oil levels in the final drive and the bike. If there up, I would have no hesitation riding it 65 miles. Don't get discouraged it may well be a simple fix. Patience bro. 

[Valkorado]

Check the oil levels in the final drive and the bike. If there up, I would have no hesitation riding it 65 miles. Don't get discouraged it may well be a simple fix. Patience bro. 

Thanks.  I'll update when I get it figured out.

[Jess from VA]

During the 65 miles (which should be fine), you might stop and make sure the rear tire is not getting oily.

[Daniel Meyer]

Wipe a finger in it and smell. Is it rear  end or engine oil. The difference is distinctive.

If rear end, probably didn't get the seal into the pinion cup.

If engine is probably is a bad rear engine seal. NOT a hard fix.

Order a new boot...the oil soaked one won't last if you reuse it. Order the seal and o-ring for the seal holder.

Pull the rear end and u-joint. (you don't need to pull the pipes)
http://www.rattlebars.com/mtz/ujoint.html

The seal is in a seal holder bolted to the back of the engine with 3 bolts. The oring goes between the seal holder and the engine.

Change the seal and oring, bolt the seal holder back on. Easy peasy!

Put u-joint back on.

To get the shaft back into the ujoint, there's a trick.

Shaft into pinion cup, seat seal.

Insert rear-end/shaft into swing arm.

Raise swing arm ALL THE WAY UP.

align/insert 4 bolts into the holes on swing arm

Wiggle the crap out of the rear end. Shaft will go home in under 20 seconds, every time. I demo this at Inzane.

If the rear end goes, in, the shaft is in the joint. Can't miss.

[Valkorado]

Wipe a finger in it and smell. Is it rear  end or engine oil. The difference is distinctive.

If rear end, probably didn't get the seal into the pinion cup.

If engine is probably is a bad rear engine seal. NOT a hard fix.

Order a new boot...the oil soaked one won't last if you reuse it. Order the seal and o-ring for the seal holder.

Pull the rear end and u-joint. (you don't need to pull the pipes)
http://www.rattlebars.com/mtz/ujoint.html

The seal is in a seal holder bolted to the back of the engine with 3 bolts. The oring goes between the seal holder and the engine.

Change the seal and oring, bolt the seal holder back on. Easy peasy!

Put u-joint back on.

To get the shaft back into the ujoint, there's a trick.

Shaft into pinion cup, seat seal.

Insert rear-end/shaft into swing arm.

Raise swing arm ALL THE WAY UP.

align/insert 4 bolts into the holes on swing arm

Wiggle the crap out of the rear end. Shaft will go home in under 20 seconds, every time. I demo this at Inzane.

If the rear end goes, in, the shaft is in the joint. Can't miss.

Wow, thanks Daniel that's the kind of info. I needed!  I did smell the oil and it was stanky.  So if that means rear end oil would that just be a matter of trying to get seal back in correctly with lifted swingarm technique?  If that's the case could I still use the old boot until I have to replace it someday?

[Daniel Meyer]

Wow, thanks Daniel that's the kind of info. I needed!  I did smell the oil and it was stanky.  So if that means rear end oil would that just be a matter of trying to get seal back in correctly with lifted swingarm technique?  If that's the case could I still use the old boot until I have to replace it someday?

Inspect the seal carefully...if undamaged, yep, it'll work. On the boot...well...squeeze it...if it's saturated or spongy or breaks, it's done for.

[Jess from VA]

Except if your remove it, a new one is easier to get back on, and they are not that expensive.

My next part order will include one, just for a backup to go along with my backup Ujoint.

[Rio Wil]

Hmmmm. I would be quite surprised if that oil is really final drive lube. .....first off, not many of the pinion cups scoop enough final drive oil to even keep the drive shaft/pinion cup splines lubed.....add to that the fact the oil would have to travel up hill inside the swing arm and then drip out the boot. I would look for a leak maybe from the rear brake m/c line or maybe the engine oil filler cap is loose or the seal around the transmission  output shaft.....is there any oil covering the outside of the boot or is it just leaking from seemingly one place from inside the boot.....

[salty1]

I just read this link, it may add to the confusion. 

http://www.valkyrieforum.com/bbs/index.php/topic,69931.0.html

[PhredValk]

Yep, an alternator O-ring fixed my oil leak, and I thought it was the shifter seal!
Whatever you do DON'T remove the alternator! Just back it out enough to replace the O-ring (if you determine that's the culprit). If you pull the alternator right out of the frame, it's a bear to get back into position. Ask anyone that's done it...
Fred.