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robert g
12-17-2007, 06:56 PM
I installed a new slave cylinder today and tryed bleeding it without success.


I first filled the resovoir with fluid all the way to the top..

I bought one of those brake bleeding tools/ vacuum testers to bleed it.

I opened the valve and pumped and pumped.

Lots of fluid came out...

Pedal still goes down to the floor...

I dont have much experience with this type of bleeding car and tool...

Please help me.. Thanks in advance...

I also read some of the old post but didnt help...

Mr._Graybeard
12-17-2007, 09:05 PM
How about reverse-bleeding the slave. Take a 3-foot length of clear vinyl tubing and attach it to the bleeder on the left front brake caliper. Feed the other end into the engine bay and position it near the bleeder on the slave. Loosen the caliper bleeder and let the tube fill with brake fluid (gravity'll do it if you're patient, or pump the brakes lightly to encourage the flow). Once it's full of fluid with all air bubbles evacuated, loosen the slave bleeder and attach the free end of the tubing to it.

Then get into the car and pump the brakes lightly -- don't pump the pedal too hard if you have an old master cylinder as you can mess up the seals. The brake fluid from the caliper will push the air bubble out of the slave and up into the reservoir, since air is lighter than brake fluid.

robert g
12-18-2007, 08:56 PM
I got it to work and fast... For anyone else in the future... Here goes....

1st install line on to new slave...

2nd fill with fluid....

3rd do not install the valve just yet... break loose the bleeder valve... and push in rod with valve open.. when you get to the end close valve. REPEAT several times. maybe 3 times... Make sure bleeder valve in pointing up.

4th Install on to trans..

5th have someone press pedal and bleed normal.. again several times... ALL ways MAKE SURE there is plenty of fluid. Doing it this way I really didnt loose alot of fluid...

yaofeng
12-19-2007, 04:19 AM
No BMW I know needs power bleeding. It is because from the brake fluid or clutch fluid reservoir to the master to the slave is is continuously sloping down. Just attach a piece of clear plastic tubing at the slave nipple after loosening. Go get a 10 minute break and you'll have pedal after coming back. If you are impatient, pump the pedal you'll aslo get the clutch back.

gale
12-19-2007, 07:32 PM
3rd ... Make sure bleeder valve in pointing up...

I'm not so sure about that. I installed mine that way, intuitively thinking the bleeder valve needed to vent the cavity from above. After taking my old slave cyl. apart, the bleeder valve needs to point down. The bleed hole in casting goes to the opposite side of the bore.

Chris'91'525i
12-20-2007, 06:03 PM
Was not sure if you meant a clutch slave cylinder a brake master cylinder or brake caliper, or what. ( I guess the brake caliper could be considered a "slave cylinder").
Only clue was you mentioned was the "Pedal still goes down to the floor", tells me it's the brakes....
I was just confused as to which car and car parts you are talking about ??
So what car do you have ??