Slave Cylinder/Transmission removal photos

[jgburns]

Jerod DeJong is helping me with a clutch replacement because we discovered the Slave Cylinder leaked DOT 4 brake fluid into the clutch housing area (while going in to drill the weep hole). Getting the transmission out is not that difficult, just time consuming.

However, without Jerod at my side, I'd be going through night sweats about getting it back together. Thanks Jerod!

For those interested in photos and some explanation to suppliment the manuals on how to get the transmission out and what it looks like, here's some overview photos.

I'll post some detail photos separately.

[zippy_gg]

Great photos John.
While you were at it, did you also replace the output shaft seal? Did it need to be replaced (sign of leakage, etc...)?

[jgburns]

Great photos John.
While you were at it, did you also replace the output shaft seal? Did it need to be replaced (sign of leakage, etc...)?I'm going to order parts tomorrow or Tuesday. I didn't notice leakage, but I'm going to replace it.

[dshealey]

I'm going to order parts tomorrow or Tuesday. I didn't notice leakage, but I'm going to replace it.

Very wise move! That seal tends to start leaking, but the more usual culprit is the O-ring on the shaft. It gets hard, and sometimes has to be picked out in pieces. Don't know why they don't use Viton there. It would be a good move to measure a new O-ring to see what size it is and get a Viton replacement.

[SmokinJoe]

I'm going to order parts tomorrow or Tuesday. I didn't notice leakage, but I'm going to replace it.
Super information John!
BTW are you REBUILDING or REPLACING the slave? My local BMW mechanic said they VASTLY redesigned / reinforced the entire slave cylinder (mid 2005 on >)to prevent the cause of failure and he suggests replacing it. He also said he has not seen one failure from the new slave..but IMO not enough 'time tested'.

[murray]

[QUOTE=SmokinJoe]Super information John!
BTW are you REBUILDING or REPLACING the slave? My local BMW mechanic said they VASTLY redesigned / reinforced the entire slave cylinder (mid 2005 on >)to prevent the cause of failure and he suggests replacing it.
That may be true but the part numbers are the same. I will be swapping my control this winter well see if so.

[blouw]

Nice pix, John.
Be really careful when replacing gearbox seals. I got to do mine again because the first time I pushed the rear input shaft seal in too far -the one where the slave cylinder goes. Good test is to tilt the gearbox after new seals are installed - should not leak.
I eventually got my local dealer to seat that seal with their special drift.
The rear main engine seal is probably worth doing as well. I installed mine by putting it on the clutch housing and pressing it in by tightening the big center nut. It will not be quite flush, so I removed the housing, put the old seal on it, tightened the nut again and when the two met, gave it about 1 1/2 turns. Should then be flush with the housing.
Another tip. when re-assembling clutch, use the actuator rod to position the spring diaphragm.

[murray]

Very wise move! That seal tends to start leaking, but the more usual culprit is the O-ring on the shaft. It gets hard, and sometimes has to be picked out in pieces. Don't know why they don't use Viton there. It would be a good move to measure a new O-ring to see what size it is and get a Viton replacement.
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[jgburns]

Very wise move! That seal tends to start leaking, but the more usual culprit is the O-ring on the shaft. It gets hard, and sometimes has to be picked out in pieces. Don't know why they don't use Viton there. It would be a good move to measure a new O-ring to see what size it is and get a Viton replacement.Jerod, are you watching? Between the bike project, work, and taking care of young kids, I can barely remember my own name. I'll try to remember to do this. Thanks for the tip David.

[jgburns]

Super information John!
BTW are you REBUILDING or REPLACING the slave? My local BMW mechanic said they VASTLY redesigned / reinforced the entire slave cylinder (mid 2005 on >)to prevent the cause of failure and he suggests replacing it. He also said he has not seen one failure from the new slave..but IMO not enough 'time tested'.I'm going to order a new part. Hopefully, it'll hold up. If it doesn't, but the weep hole works, the job won't be nearly as bad.

[jgburns]

Brian, I'm going have my dealer install the seals in the transmission cover that's removed. Thanks for the additional tips.

Nice pix, John.
Be really careful when replacing gearbox seals. I got to do mine again because the first time I pushed the rear input shaft seal in too far -the one where the slave cylinder goes. Good test is to tilt the gearbox after new seals are installed - should not leak.
I eventually got my local dealer to seat that seal with their special drift.
The rear main engine seal is probably worth doing as well. I installed mine by putting it on the clutch housing and pressing it in by tightening the big center nut. It will not be quite flush, so I removed the housing, put the old seal on it, tightened the nut again and when the two met, gave it about 1 1/2 turns. Should then be flush with the housing.
Another tip. when re-assembling clutch, use the actuator rod to position the spring diaphragm.

[dshealey]

Super information John!
BTW are you REBUILDING or REPLACING the slave? My local BMW mechanic said they VASTLY redesigned / reinforced the entire slave cylinder (mid 2005 on >)to prevent the cause of failure and he suggests replacing it. He also said he has not seen one failure from the new slave..but IMO not enough 'time tested'.

It would be a bit of a task to re-build the cylinder, as the seal is not available as a seperate part from BMW. One may be able to second source it. However, the bearing in the end of the piston is likely another culprit in causing them to fail, as one of mine did fail because of the bearing seizing and causing the piston to spin in the cylinder. If I had a slave leaking I would not attempt a re-build even if the piston seal were available, as brake fluid getting into the bearing would probably wash out/dilute the grease in the bearing causing it to fail next.

The clutch master cylinder does have replacement parts available, but not the slave.

[Nitrodoc]

HI Guys,

Similar story here. I am no mechanic but the exact same clutch failure occurred to me at only 18001 miles. Also out of warranty. In the middle of 7000 mile 3week run I notice oil under the stand, I drive 180 miles out of my way to take it Ironhorse in Tuscon. The dealer charges 1780 smackaroos and notes that my problems were multifold. His narration included his observation of leaking seals etc and that my rear end was leaking also from improperly tightened plugs during my 12000 scheduled maintenence. Parts amount to 300 the rest labor. The service manager suggests calling bmwoa for some mercy because in his opinion this should n0t be happening at this low milage perhaps after 60k.

The district bmwoa gives no consideration other than I can get 500 off a new bike if purchased within 30 days.


The clutch is slipping again and now I am home in Florida.

Bmw will warranty the parts but... this blows. Dont think that I should have to eat the labor again for a problem that BMW knows should be a recall.This problem is mentioned frequently in this post does anyone have a suggestion.