getting the brake cam bush out of the drive box

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As title. Anyone care to shed some light on the best way to go about this on my G/S?

Present bush is scored and oil leaks past the o rings.
 
Hi, recently had the same problem, ended up taking the final drive off and had an engineer press out the 2 bushes i had in mine. Yours may only have the single long sleeve and this may mean splitting the final drive and replacing it.
You need to see if you have the 2 bushes or single long one. The newer long sleeve will need sealing with a good compound and setting before reassembly of the brake cam and washers. The 2 shorter bushes are also available but the single long one would be the best way to go.
The small o rings are pennys to replace but if replacing the 2 small bushes for the longer one you will probably only need 2 o rings as 4 will cause too much interference on the cam..
I hope this helps,
Steve
 
I seem to remember I have the 2 bushes. So it's possible to press these out without splitting the box?
 
I seem to remember I have the 2 bushes. So it's possible to press these out without splitting the box?
My quess is if you have leaks because the o ring doesn’t seal properly due to scoring then you have a two piece sleeve/bush. I’ve not done it before as I’ve always stopped leaks with new o rings but I believe the one piece sleeve/bush was an upgrade by BMW to solve this problem and can be retro fitted.
 
My quess is if you have leaks because the o ring doesn’t seal properly due to scoring then you have a two piece sleeve/bush. I’ve not done it before as I’ve always stopped leaks with new o rings but I believe the one piece sleeve/bush was an upgrade by BMW to solve this problem and can be retro fitted.
You can ,as said above replace the two bushes with a single long one,
Iirc you need a paralever one.
You will struggle to press them out without splitting though,
I can’t think that you could press in any other direction apart from inward.:nenau
You could try cutting a thread on the inside and screwing a bolt into the bush,then you could drive it out,or it may even release while cutting the thread,
BUT,it’s a thin wall bush and may well just grip more into its housing.
For the cost of a new gasket I’d just open it up and do it on the press:thumb2
 
My quess is if you have leaks because the o ring doesn’t seal properly due to scoring then you have a two piece sleeve/bush. I’ve not done it before as I’ve always stopped leaks with new o rings but I believe the one piece sleeve/bush was an upgrade by BMW to solve this problem and can be retro fitted.


That does sound right.

I've change the o rings once and it did stop leaking, but not for long.
 
You can ,as said above replace the two bushes with a single long one,
Iirc you need a paralever one.
You will struggle to press them out without splitting though,
I can’t think that you could press in any other direction apart from inward.:nenau
You could try cutting a thread on the inside and screwing a bolt into the bush,then you could drive it out,or it may even release while cutting the thread,
BUT,it’s a thin wall bush and may well just grip more into its housing.
For the cost of a new gasket I’d just open it up and do it on the press:thumb2

I'll whip the box off and split it, then get the bush pressed out. might try splitting it myself to see if I can shift it first.
 
Perhaps I was lucky.

I made a tool fitting into the new bush, and using M8 or M10 studding pulled the new one piece bush into place whilst pushing the old 2 bushes out.

No splitting of drive.

Have a search in here. I did a write up with photographs 3 or 4 years ago.
 
Perhaps I was lucky.

I made a tool fitting into the new bush, and using M8 or M10 studding pulled the new one piece bush into place whilst pushing the old 2 bushes out.

No splitting of drive.

Have a search in here. I did a write up with photographs 3 or 4 years ago.
Interested to know how ,as you are pushing/pulling into a void,?unless you used a centre support.
A new gasket is less than £5:confused:

With advantage of giving the drive a health check,and clean.
 
Just a reminder if you do decided to to split the case that the large bearing should be a tight fit on the crown wheel and in the cover, and the crownwheel wheel and cover should come off as one.
In the last couple of videos / how too's I have seen the bearing was loose enough in the cover that the cover came off without disturbing the crown wheel.
This passed without comment, and the cover was reinstalled without the required Loctite product and the bearing flapping around loose!
If yours is the same Loctite bearing fit is required, just dont loose any of the shims and work out how you are going to get the bearing hard up against the shims before the Loctite sets.
 
Just away at the moment, will dig out photos and post up over the weekend
 
Took the drive box off this afternoon and attempted to get the cover plate off. No luck - it's like it's welded on :(
 
I was hoping that's why they were for as I did try that as hard as I dared with such little M5 threads yesterday and it didn't budge the cover. I think maybe some pillock has glued it on with sealant.

Might try a bit of heat on it today.
 
Maybe the PO used some form of Loctite on the joint instead of a gasket, similar to joint between the monolever and the final drive.
The manual does talk of Loctite, it is just not that clear whether it goes on the bearing or on the cover joint.
Or maybe he did it that way in an attempt to tighten up the clearance on the large bearing!
 
Done it now. Amazed how much grief those threads will take.

No sign of sealant, but the gasket was well and truly stuck to both parts and ripped apart down the middle leaving 50% stuck on each side like concrete.

Crown wheel bearing still tight in the cover.
 
This is what I did.

Puller with spigot

Larger dia needs to be a shade under the o/d of the bush, as during the process this will need to go into the bore of the final drive housing.

The small dia needs to be a snug fit into the bush.

Assemble puller on the left and a piece of suitable tubing on the right to capture the 2 bushes as they come out.

Once one bush has come out, then re-assemble with the pulling tool into the new 1 piece bush on the left and continue pulling.

Didn't use any heat, and the bushes came out quite easily.

Re-assemble with O rings and HMP grease and a new felt washer over the shaft / behind the lever arm.

Did this a few years/miles ago and cured the oil leak from the brake spindle.

Just remember that you will need to lubricate the spindle manually at service time as it's not splash fed any more.
 

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Thanks.

Just to clarify, you pulled both bushes out in one go to the right hand side of the bike? Kind of wish I'd thought of a way of doing that before i split the box :blast
 
Yes. Both bushes were pulled through into the tube on the right.

I then made a 1 piece bush to the same o/d and i/d dimensions.

The new bush was then pulled into place by the tool with the spigot.

I had replaced the o rings a number of times and just seemed to me that the splash effect was causing pressure to push the oil out. The breather was checked every time and was clear.

You might have to shorten the M6 level plug to prevent it bottoming out on the bush and distorting it.

Fit a new felt bush on the shaft before replacing the operating lever.



Since doing this mod I have not had any further problems.
 


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