Gear box leaking R1150GS

**Ruta40** · #1 21 Jul 2004

I have a R1150Gs year 2001 with 36.000 kms. Three months ago I had the gear box opened in order to change the seal for the ROD (the axis that pushes the clutch). they put it together and then the leaking started through the oil seal that goes in the rear end of the drive shaft. We have tried four times to stop the leacking without any success. Any sugestions??

Thanks,

Camilo Delgado
Ruta 40

**Grant Johnson** · #2 22 Jul 2004

Camilo,

What have you done so far in your attempts to stop the leak?

The usual cures are to replace the appropriate seal, and make very sure that the shaft that it is sealing isn't damaged in any way, or it will just destroy the seal. Also of course make sure that the vent isn't clogged or heat will build up pressure and force oil out.

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Grant Johnson

Seek, and ye shall find.
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One world, Two wheels.
www.HorizonsUnlimited.com

**Ruta40** · #3 22 Jul 2004

Quote:

Originally posted by Grant Johnson:
Camilo,

What have you done so far in your attempts to stop the leak?

The usual cures are to replace the appropriate seal, and make very sure that the shaft that it is sealing isn't damaged in any way, or it will just destroy the seal. Also of course make sure that the vent isn't clogged or heat will build up pressure and force oil out.

**Ruta40** · #4 22 Jul 2004

Grant,

Thanks a lot for your prompt reply. We have done all you said (we have changed three times the oil seal) and also we checked vent and it is good (not clogged).

Anyone has have any similar problem?

Regards,

Camilo Delgado
Ruta 40

**Grant Johnson** · #5 22 Jul 2004

Just to be sure - this is the seal at the back of the transmission, or the back of the driveshaft near the rear wheel?

Is it a big leak, or just a wet misting on the case?

What kind of oil?

Are you SURE there is no sign of wear, grooving, or scratches on the shaft? ANY damage or wear will cause a leak. How long does it take the leak to start after a new seal? Is it the CORRECT seal? Right way around? (Spring side to oil is usually correct)

Grant

**Ruta40** · #6 27 Jul 2004

The leaking is at the seal in gear box close the driveshaft and the right footpeg. it is a big leaking

Oil is Castrol Syntrax 75W 90 Syntec oil.

What we have`t told you is that they opened the gearbox first time to replace this seal when the gear box was cold, but the heated it with a welder (oxigen flame). since then, every time they try to put it together there is a leak in that seal.

Is there any chance that the gear box was "missassembled"? could this somehow explain a small vibration that I feel in the bike through the footpegs?

Thanks a lot

Camilo Delgado

Quote:

Originally posted by Grant Johnson:
Just to be sure - this is the seal at the back of the transmission, or the back of the driveshaft near the rear wheel?

Is it a big leak, or just a wet misting on the case?

What kind of oil?

Are you SURE there is no sign of wear, grooving, or scratches on the shaft? ANY damage or wear will cause a leak. How long does it take the leak to start after a new seal? Is it the CORRECT seal? Right way around? (Spring side to oil is usually correct)

Grant

**Grant Johnson** · #7 27 Jul 2004

A small vibration in the footpegs is pretty normal. If new, it could be a sign that the driveshaft is going. Unlikely to be the gearbox if it works well otherwise.

Heating the gearbox with a torch is necessary to get the cover off on most BMW boxes. I've never done an R1150 so can't say for sure. But heating the case shouldn't be a problem, and certainly wouldn't affect a new seal.

There has to be some damage to the seal or it's mating surfaces, or it's installed backwards, or the bearing is bad and the shaft is moving around and overstressing the seal.

Were you using synthetic before the gearbox rebuild? If not, it could be that the seals just don't like that oil. Try using non-synthetic oil, just regular 80W-90 geearbox oil as a last try, and if that is ok, try a different synthetic.

Other than that, without looking at it I can't help much more I'm afraid.

------------------
Grant Johnson

Seek, and ye shall find.
------------------------

One world, Two wheels.
www.HorizonsUnlimited.com

**John Roberts** · #8 27 Jul 2004

Hi
The bit about having used an Oxy-accetylene flame bothers me- with such a fierce and localised flame it would seem a strong possibility that the seating for the seal has been damaged. Try using a sealing compound on the seal where it beds on the casing, Loctite, for example, will probably have something suitable.
Good luck

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Johnefyn