Boxerworks.com

R100 '84

So I recently did the input spine lube, and in that process had the drive shaft boot disconnected. After the job I noticed a leak at the boot. I tightened it up and did another drain and refill of the gear oil in the shaft. The leaked stopped for a couple of weeks but this morning there was a stream down the shop floor. Looks like it is the front (trans) side of the boot that is leaking. I'm wondering if the hose clamp is failing. It's a PIA to keep draining and refilling. Boot is in good shape. Will take weeks to get a new clamp. The clamp seems to tighten up OK. Any thoughts?

If the clamp tightens it's not failing. Either the boot does have a small hole or it's not seated properly.
Wash all oil from the boot and try to see exactly where it's coming from.
A small mirror might help you see what's going on.

For mystery leaks sometimes it helps to get the area clean clean clean and then dust that area with baby powder or cornstarch. Oil will leave a visible trail.

I cleaned and re-seated boot and clamp. I put some low strength lock tite on the the threads of the clamp. I checked trans fluid level and it was full. I lost about a third of the gear oil in the drive shaft. I noticed that the other clamp (drive shaft side) was on the loose side. Once I refilled the drive shaft, I made a gauge out of a twist tie crimped to a electrical connector and noted the depth of oil for reference. I think maybe I was worried about striping the threads on the clamps. I went tighter this time. Now I need a road test. Thanx for you input!

SteveD wrote: ↑Sat Aug 12, 2017 11:27 pm I don't know why this seems to work, but in the absence of any obvious cause or science, I've always had the fastener part of the clamps at b/w 11 & 1 o'clock. That puts the flat aspect of the clamp at near 6 o'clock and being that's where fluid will tend to settle I'm thinking the seal might be that little bit more uniform. I do it on the carb clamps too.
It's just my habit and I'm unsure why I started doing that in the first place. I think I read it on the internet somewhere!

I thought about that orientation, keeping the overlap of the clamps on top, but I've never had them leak before in 46 years of Air Head ownership. But maybe if my attempt doesn't work....

Came down to the shop and there is gear oil under the bike.

And it's coming from where exactly? You should be able to pinpoint the leak.

ME 109 wrote: ↑Sun Aug 13, 2017 3:16 pm And it's coming from where exactly? You should be able to pinpoint the leak.

It just looks to be leaking out of the sealing area of the transmission where the boot attaches with the clamp. Are these boots the same size opening on both sides? I have a new one, but it's hard to tell. I have the seams of the boot at the top and bottom.

The clamp, where it screws together is about 8 oclock. It doesn't seem to be leaking from the shaft side of the boot. These clamps are quite soft so you would think they would conform to the shape of the boss.

But if it is leaking even before I ride it then what? the boot seems to fit on the boss OK. Is there a front and back to the boot? Man...I do not want to take this all apart again. Maybe try Steve's clamp orientation method.

The boots do have notations for front (getriebe for transmission) and top (oben).

Kurt in S.A.