Oil in boot

Cobbster · Post by **Cobbster** » Sat Oct 13, 2007 5:02 pm

Hi all,
After some vigorous cleaning of my backend, oooh err missus, I noticed I had dislodged the rubber boot between the final drive and the swing arm. Ahh I thought, time to have a look inside. I noticed a very small amout of oil lying inside, not even enough to run into the boot, but a drop all the same. A sniff of the offending lube and I knew it was either from the gear box or final drive as it had the distinctive niff of Mobil1. Nothing had leaked out of the boot cos there wasnt much to leak but need I be worried and where was it likely to have come from??.

Thanks as always, Cobbster

bigblackfalco · Post by **bigblackfalco** » Sat Oct 13, 2007 5:42 pm

Could be getting sucked out through the gearbox output shaft seal or seeping out from the seal located behind the castlenut in the bevel box.
Sounds like it is at very premature stage and is just down to hot oil going a long way, and it'll prob be made worse by the fact that the synthetic oil you are using is probably extremely thin.
I'd keep my eye on it. Don't try fixing until it's a major problem; I've seen these bikes seep oil for many thousands of miles.
Bailey.

Jason M · Post by **Jason M** » Wed Oct 17, 2007 7:38 am

bigblackfalco wrote:Could be getting sucked out through the gearbox output shaft seal or seeping out from the seal located behind the castlenut in the bevel box.
Sounds like it is at very premature stage and is just down to hot oil going a long way, and it'll prob be made worse by the fact that the synthetic oil you are using is probably extremely thin.
I'd keep my eye on it. Don't try fixing until it's a major problem; I've seen these bikes seep oil for many thousands of miles.
Bailey.

Ditto that - my GS is pissing oil out the rear gearbox seal and running down into the boot, out the boot, and all over the final drive. It's been doing it for months and months. I just top up the gearbox oil

I've got to round to doing the bearings in a spare gearbox then swap them over, but like Bailey says. A little bit of hot oil goes a long way and makes a big mess.

Jason

Cobbster · Post by **Cobbster** » Wed Oct 17, 2007 8:33 am

Hi all,
I've kept an eye on it and things have not got any worse over the past few hundred miles. As you say a little oil goes a long way. Iv'e posted this concern on the Pelican parts forum and had much the same response so as for now I'm not going to worry or do anything about it until it becomes a real problem. My neighbour has an 1150RT which the same leaking gearbox seal. It went on for thousands of miles before he eventually had it fixed at a local independant BMW specialist, cost just buttons so no real shocks coming my way.

Thanks to all, Cobbster.

Jason M · Post by **Jason M** » Wed Oct 17, 2007 12:44 pm

Cobbster wrote:Hi all,
I've kept an eye on it and things have not got any worse over the past few hundred miles. As you say a little oil goes a long way. Iv'e posted this concern on the Pelican parts forum and had much the same response so as for now I'm not going to worry or do anything about it until it becomes a real problem. My neighbour has an 1150RT which the same leaking gearbox seal. It went on for thousands of miles before he eventually had it fixed at a local independant BMW specialist, cost just buttons so no real shocks coming my way.

Thanks to all, Cobbster.

Hate to just pee ever so slightly on your parade there mate, but changing the seal on the gearbox of a S will not cost just buttons... unless they're made of gold! Getting the gearbox off an S is a bitch of a job involving the dismantling of most of the bike in order to remove the CFrame and thereby access the box. I think it's a lot easier on an RT - I think someone told me you can just swing a load of the back end out the way and get to it. Hopefully it'll just continue weeping and not get any worse.

Jason

Cobbster · Post by **Cobbster** » Wed Oct 17, 2007 3:41 pm

Hi,
The gearbox on an S as far as I'm aware does not have to be removed to access/change the output drive shaft seal, neither does the C frame need to be removed. Although fiddely once the swing arm is out of the way the seal can be extracted and replaced while the gearbox is in place. The input seal is a completely different kettle of fish with full gearbox removal required.

The RT's seal is acctually a bit harder to get at but a full service, V belt change, tappet adjustment, throttle body balance and output seal change came to less than £300 at a local independant bmw repairer. I'm going to see them next week for a quote which I'll pass onto the forum.

Cheers, Cobbster.

Jason M · Post by **Jason M** » Mon Oct 22, 2007 2:29 pm

Cobbster wrote:Hi,
The gearbox on an S as far as I'm aware does not have to be removed to access/change the output drive shaft seal, neither does the C frame need to be removed. Although fiddely once the swing arm is out of the way the seal can be extracted and replaced while the gearbox is in place. The input seal is a completely different kettle of fish with full gearbox removal required.

The RT's seal is acctually a bit harder to get at but a full service, V belt change, tappet adjustment, throttle body balance and output seal change came to less than £300 at a local independant bmw repairer. I'm going to see them next week for a quote which I'll pass onto the forum.

Cheers, Cobbster.

That's good to know, guess I didn't think too hard about that