Clutch slave cylinder let loose E34 M50

[bissellh]

I removed the clutch slave cylinder to gravity bleed it and replaced it. When I pressed the clutch pedal to check for air in the line, the pedal went straight to the floor and brake fluid started dripping out of the clutch housing onto the ground.

My clutch slave hyper-extended and came apart. I had to fish out the parts through the small hole in the clutch housing and put it back together again. My guess is that I missed the clutch release lever with the slave cylinder piston rod. Of course, if it was that simple I would not be writing this thread.

At the same time I was gravity bleeding the clutch salve cylinder, I replaced the oil pan gasket. It was my first time and I had trouble getting the oil pan off because I was unaware of the 2 recessed bolts at the back of the oil pan. I ended up loosening the bolts that hold the clutch housing to the engine block and prying the the two apart in an attempt to free the oil pan. Please do not cringe too much. I thought perhaps there was a lip on the back of the oil pan that I had to set free. Besides, my working conditions are not very good. I have cramped quarters on jack stands and bad lighting. It is hard to see when the sun is glaring outside and it is dark under the car.

Anyway, while I was fishing out the parts I noticed that the release arm for the clutch had a lot of play in it. I can move it vertically about 1/4". Is it supposed to to have tension in it from a spring? Mine just swivels horizontally with no tension.

I think it might be possible that I dislodged the release arm. If the clutch release arm is not held in very tight, may I have dislodged it while tapping the housing back towards the engine to bolt it back to the engine? I have never seen the inside of my tranny/clutch housing before and do not know. Any one have enough experience with the clutch assemly to know if there might be a problem in there that I need to correct?

[yaofeng]

Don't remember now. I think there is some play on the clutch bracket. It slips into the shaft riding on the TO bearing. See picture. I doubt you dislodged anything.

http://i21.photobucket.com/albums/b274/yaofengchen/BMW_95_525i/DSC_1579.jpg

Same thing happened to me when I bled the clutch after replacing it. I just put the push rod back and crimped the edges of the slave housing. It was crimped anyway. That was two years ago. It has held since.

[Dave M]

I can'r see how you'd miss the arm and dhighly doubt its even possible to knock that sucker off course. Its pretty simple in design (thanks for the pic yaofeng) and will have a bit of play as it just sits in front of the release bearing on the input shaft. When I swapped out my engine, the slave was hanging down free and a friend hopped into the car and, of course, pressed the brake. Bits of slave and fluid shot everywhere. I thought I was in $hit, but managed to piece it back together. Just make sure the crimpy thingy is pressed i good and solid or it will pop off again.

Good luck with it,

Dave

[bissellh]

Don't remember now. I think there is some play on the clutch bracket. It slips into the shaft riding on the TO bearing. See picture. I doubt you dislodged anything.

http://i21.photobucket.com/albums/b274/yaofengchen/BMW_95_525i/DSC_1579.jpg

Same thing happened to me when I bled the clutch after replacing it. I just put the push rod back and crimped the edges of the slave housing. It was crimped anyway. That was two years ago. It has held since.

Thanks for the reply. The picture is especially helpful.

I did not even have the transmission off the car. I just separated it from the engine block about 1/2" - 1". Is there supposed to be pressure on the release arm? Mine is just swiveling horizontally in the breeze.

[bissellh]

I can'r see how you'd miss the arm and dhighly doubt its even possible to knock that sucker off course. Its pretty simple in design (thanks for the pic yaofeng) and will have a bit of play as it just sits in front of the release bearing on the input shaft. When I swapped out my engine, the slave was hanging down free and a friend hopped into the car and, of course, pressed the brake. Bits of slave and fluid shot everywhere. I thought I was in $hit, but managed to piece it back together. Just make sure the crimpy thingy is pressed i good and solid or it will pop off again.

Good luck with it,

Dave

I recently did a clutch job on the 1984 Porsche 944 that I am refurbishing. The release arm was bolted in very securely on that car. I could not imagine that the release arm in my BMW is just sitting there waiting to be dislodged.

I can't imagine missing the arm with the piston either. But, stranger things have happened. It was getting dark night before last when I replaced the clutch slave cylinder.

The release arm is just swiveling freely in the horizontal direction. Shouldn't there be some pressure on it toward the hole in the housing? I only had the transmission separated 1/2" - 1" from the engine block. Perhaps I needed to preset the position of the release arm before bringing the transmission and engine back together and bolting them down!?!?!

[yaofeng]

I thought you are just doing the slave. No? It seems you are removing the gear box too. I am confused.

In case you are not and if you have separated the bell housing from the engine by 1/2", there will be that much play on the clutch release bracket. Actually there will be more because of the lever arm.

[bissellh]

I thought you are just doing the slave. No? It seems you are removing the gear box too. I am confused.

In case you are not and if you have separated the bell housing from the engine by 1/2", there will be that much play on the clutch release bracket. Actually there will be more because of the lever arm.

Testing! Testing!

I have been trying to reply since last night, but the web site just keeps hanging. I thought I would try a shorter respose to see if it would go through.

[bissellh]

I thought you are just doing the slave. No? It seems you are removing the gear box too. I am confused.

In case you are not and if you have separated the bell housing from the engine by 1/2", there will be that much play on the clutch release bracket. Actually there will be more because of the lever arm.

While replacing the oil pan gasket, I unbolted the engine and tranny thinking I needed to in orer to release the oil pan. I had overlooked the two recessed bolts at the rear of the oil pan. I jacked up engine to remove the oil pan before bolting the engine and tranny back together. I think the engine and tranny would have separated at a weird angle. Then I put everything back together.

I do not think I missed the release arm with the slave cylinder piston. The release arm release arm swings freely with no resistance. Shouldn't there be some pressure on the release arm? I am concerned I either broke something or something moved out of position.

[bissellh]

Problem resolved! I probably missed the clutch release arm causing the clutch slave cylinder to let loose. I put it back together and installed it again making sure that I could feel resistance against the release arm as I installed it. I bled it and it works fine.

Does anyone think it would be wise for me to spray some brake parts cleaner into the clutch in order to clean out the highly corrosive brake fluid that would have shot everywhere when the clutch slave cylinder let loose?

Thanks for the responses!

[Dave M]

Good to hear you got it. Hard to imagine missing the arm, but I guess the amount you moved the tranny may have allowed it. I don't see a need to try cleaning up any brake fluid. You may have ended up with some on the back of the pressure plate, which would already have trickled down into the bell housing. Your release bearing wouldn't like to see harsh solvents either. Its time to drive it.

Dave