Final drive breather leaking? why?

[scud]

I am currently in SE France near Carpentas with my 1150GS 2002. I have limited interent access, so will check back in the morning for any ideas....

In the last couple of days, I've noticed that the final drive breather appears to be the source of considerable oil leak, contaminating the disc and tyre.

What could be causing this? it never leaked in the UK. It's been hot here (30+) and I've been in the hills on lots of twisties - would the oil "expand and be thrown out the breather?

I've checked the fill level on the final drive unit and the oil is at the top of the filler plug hole.

I don't want to change the pads until I know what's causing this.

Not sure if this is also relevant, or linked to it, but I had to top up a fair amount of oil in the gearbox before I left.. a fair amount leaked out at somepoint from somewhere, but I never was able to find out where from nor why?

Any help gratefully received! Cheers!

 

[Stewart H]

It may be slightly overfull? I have seen my airhead do the same with certain brands of oil and not others too.

 

[Timolgra]

It won't be the heat, I've had my 1150 in 50deg C with no probs.

Assuming it has the correct oil...you could check the O ring other than that it's a bit of a mystery BUT are you sure it's not coming from the final drive oil seal?

 

[scud]

It won't be the heat, I've had my 1150 in 50deg C with no probs.

Assuming it has the correct oil...you could check the O ring other than that it's a bit of a mystery BUT are you sure it's not coming from the final drive oil seal?

Nope, not really sure... I'll try and post a pic in a bit, but the breather looks the "wettest" area and it's also the highest bit that's wet.... ?

 

[Grizzly]

oil type?

Are you sure you've got gl5 grade oil in bevel box? gl4 grade does not have an anti-foaming additive which is essential for the GS. gl4 could foam up & leak at breather but if you've leaked as much as it sounds I would expect the oil level to drop as it only holds 250ml anyway.

Cheers........Grizzly

 

[street_moto]

On the 1100gs, the final drive is filled to the bottom thread of the filler plug hole, are you sure the 1150 is supposed to be full to the top? Quite a bit of extra oil in there if it's not supposed to be!
Hope you get it sorted!

 

[stavross]

If it's at the top of the filler hole it's overfull - should be to the bottom of the thread as stated previously.My old 1150 always chucked it out when overfull Drain some off, clean the area up & see how it goes.

 

[scud]

Brilliant... cheers!

I'll let you know how I get on.......

 

[scud]

Ok,

It's definately GL5 oil I put in it.

It's been standing over night, so I undid the filler for the final drive and oil positively pushed it'self out. It wasn't this full the other day when I checked it.

So the extra oil must have come from somewhere... I checked the gearbox oil level and cannot see the levl of the oil, although the metal inside appears wet with oil.

Is it possible for the gearbox to have blown a seal and then the oil travel down the swingarm and fill up the final drive unit? aren't there different seals in the way?

I'm near Carpantas in SE France... anyone know where I could take it?

Cheers

 

[hank]

Could just be a blocked breather. On the top of the final drive unit you will see the black plastic breather cap. Carefully pry it off with two screw drivers and clean the filter inside with brake cleaner. If the filter is blocked it causes a build up of pressure inside the final drive.

 

[Steptoe]

Cut the cable tie holding the paralever gaitor and pull the gaitor back and see if lots of oil runs out - It should be full of oil if you think it's leaking out of the gearbox into the final drive -

which would also mean as well as the gearbox output seal leaking the final drive input seal is also fecked.

Also pour some gear oil into the gearbox and see much oil you need to fill it up to the filler.

It'll save all the guessing.

 

[tosh23]

bump bump

 

[MattW]

bump bump

Did you do this:

Cut the cable tie holding the paralever gaitor and pull the gaitor back and see if lots of oil runs out - It should be full of oil if you think it's leaking out of the gearbox into the final drive -

which would also mean as well as the gearbox output seal leaking the final drive input seal is also fecked.

Also pour some gear oil into the gearbox and see much oil you need to fill it up to the filler.

It'll save all the guessing.

Steptoe fixes BMW's for a living - it's worth listening to his input