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docc

rear drive seal

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The big seal on my rear drive has been dripping. I have a new seal, but need to be sure how to remove the old one.

 

Can it be simply pried out and the new one tapped in?

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The big seal on my rear drive has been dripping. I have a new seal, but need to be sure how to remove the old one.

 

Can it be simply pried out and the new one tapped in?

That is pretty much what I did. I used heat to help as there was a bearing that came out with it as I recall.

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Docc,

Go to an automotive paint store and buy a ScotchBrite pad to polish the seal surface of the shaft then clean with Brakekleen. Lubricate the seal and shaft surface upon reassembly.

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Ok, then, good to go! (sort of :glare:)

 

The seal's out and in. Thanks for the pointers. I decided to pull the drive and do the job on the bench. Easier, I think, than lying on the floor.

 

While out, I cleaned up the U-joints and figured I'd go after them with the grease gun again.

 

Indeed, the grease fittings can go missing: Now to try and find a replacement. I suppose it is angled, what, 45 degrees? And this is pipe thread or something otherwise special?

IMG_0088.JPG

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Look at the other fitting on the opposite joint. Probably a 45 degree fitting & metric thread. Take the other fitting with you to match it up. Go to an established auto parts store for the correct fitting.

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Thanks for the tips! The seal changed pretty easily. I still haven't run it in to see if it holds redLine.

 

During the cleanup I found the rear U-joint had spit off its Zerk fitting. I couldn't find one angled so fitted a straight then tried to grease it with a needle. Between that and the front, the whole thing is a fiddly greasy mess. I do think I managed to get some grease in the joints this time.

 

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Ok, then, good to go! (sort of :glare:)

 

The seal's out and in. Thanks for the pointers. I decided to pull the drive and do the job on the bench. Easier, I think, than lying on the floor.

 

While out, I cleaned up the U-joints and figured I'd go after them with the grease gun again.

 

Indeed, the grease fittings can go missing: Now to try and find a replacement. I suppose it is angled, what, 45 degrees? And this is pipe thread or something otherwise special?

Yes, mine is angled about 45 degrees (ummm, wait a sec). Dunno what the threads are but they are bound to be metric equivalent of pipe threads I imagine. Not near my bike, so I can't look.

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Docc,

You probably need a 6mm 1.0 thread pitch w/45 deg. angle grease fitting.

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The only M6-1.0 45 angle available to me locally is much too large for the space. I tried to "see" the one in the front, but *ha.* Even with lighting and a dental mirror on the end of a long hemostat, I could only focus on the little bugger with one eye; and even then through a less than optimal segment of my corrective lens.

 

Even after ten years, the damn U-joints remain elusive. In fact, I think I doubled my vocabulary today . . .:bbblll:

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Docc,

mark the driveshaft at the sip yokes so you can install it the way it came off and remove that portion (of the driveshaft) and take it with you......... after looking at it I see it's the rear joint. Remove the two pinch bolts that hold it to the splined shaft. It should slide right off.

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So, I suppose an update is rather overdue. I always appreciate when posters come back with "the rest of the story."

 

The big seal went in fine and contained about 90% of the drip. I tried to source a replacement shaft just to be certain about it, but never could get one around. Even with a $600 USD promise.

 

Yet, the u-joints don't grind or play, so I decided to keep them intact (and the alignment marks aligned), pull the rear drive, and have the inner seal replaced.

 

After carefully searching for a proper "factor," I delivered the piece up. Now, I had read about the procedure to use heat and drop the drive onto a block of wood to dislodge the internals. I figured I would pass on this and hire it done properly.

 

After two weeks, the fellow informed me that it would take a special bearing puller, and the "hot drop block" method had cracked the case. Cosmetic, says he, but not good. The drive would be going to Harper's in Kansas, USA, and he would try to address the crack.

 

So I says, "The crack is at like 10:00, 9:00, what?"

 

"9:00," he says

 

(Long post, now, I know, but it's been going on a year and a half)

 

As it turns out, the back flange (or "bell") of the rear drive snapped almost completely off. The "crack" started at about 11:00 through the mounting web of the torque arm and broke downward along the back of the drive to, say, 7:00 about an inch from the edge. The piece almost completely broke off!

 

Now, this fellow has been working on Guzzis for half a lifetime. His observation is that the earlier drives didn't have as big of a flange or as deep of a "bell" or "cone" if you will. The block he's dropped so many earlier drives on snapped this one.

 

So, new seal in (from Harper's), crack welded, I sanded, grinded, filled (JBWeld), sanded, shaped, primed, sanded, painted, sanded, clear coated . . . garage basement plastic surgery.

 

500 miles now and no leak! And the cosmetics are not terribly bad (this is not my show bike).

 

I don't suppose I'll be carelessly overfilling the rear drive with Redline Heavy and I wonder if the "heat and drop" dis-assembly method may be, well, not so good for these later/ pre-CARC rear drives.

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I just did a google search to find out what to do about my leaky rear drive . . . and found my own thread! Perhaps flattering , but otherwise not good. Two weeks out from the Spine Raid and the blasted thing still drips. Tried Lucas "Hub Oil" made for just this thing, and which seemed to help, but still drippy.

 

I suppose I'll try to fit a new big seal and hope for the best. :angry:

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I take it that you have checked that the breather is not blocked and that the leak is definitely from the big seal ?

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I take it that you have checked that the breather is not blocked and that the leak is definitely from the big seal ?

 

Definitely have cleared the vent. Just cleaned her up with the wheel off and rode about 50 miles. One big drip hanging from the large seal and the run coming from the right side. The large left seal is easy to do, but where is the other drip coming from?

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DSCN2182.JPG

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Have you changed brand of oil, looks like both the inner and outer seal are leaking. Is the pinion seal leaking too for a full house?

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