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Clutch master cylinder failing

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Old 11-29-2004, 04:42 PM
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indefactorX
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so the slave comes all the way off?
Old 11-29-2004, 04:52 PM
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No - you remove the attaching bolts, but do not loosen or remove the hydraulic line. Move the cylinder away from the bellhousing enough to grip the rod with needlenose ViseGrips or pliers, and push it firmly into the body of the slave cylinder.

Before you do that, you might try the Kempf method of bleeding. Basically, pull the guts of the master cylinder back out of the bore just enough that the very top of the tilted piston seal clears the lip of the cylinder bore just enough to let any trapped air escape.

Do that first, then do the slave cylinder rod push-back exercise, reassemble everything, and bleed normally again. Usually gets all of the air out pretty quickly.
Old 11-29-2004, 05:24 PM
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hmmm the kempf method you mention is something i was thinking about trying but wasn't sure if it was a good idea, i think i'll try that now that i know, then i'll try the slave


thanks wally
Old 11-30-2004, 05:33 PM
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Ok, i tried both methods, Only one problem

when i unbolted the Slave cylinder it came completely out and i don't know if i can get the pushrod back into position,,,,, how do i know that it is seated correcly?
Old 11-30-2004, 05:34 PM
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also i forgot to mention, my car has just developed a puddle of brake fluid under the car from the start of this project, what should be the first thing i check, ( this was there before the removal of the slave cylinder
Old 11-30-2004, 05:54 PM
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hupp
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From what area is the leak coming from. There are many fittings in the system that can possibly be leaking. The clutch line also has a rubber section that may have degraded and started leaking.

To install the slave, push the rod in and place slave back into place. Once into place the end of the rod should rest in the cup in the end of the clutch throwout lever. Look into the hole the bottom of the bell housing and you should be able to see the end of the clutch lever at the rear of the hole. The small amount of slack in the slave line should allow you to manipulate the assembly into the proper position.
Old 11-30-2004, 05:59 PM
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got it! thanks hupp

is it possible that the line connected to the master cylinder popped off??? how can i check this because i can't see any end of the master from under the car
Old 11-30-2004, 06:14 PM
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There is a small rubber hose (covered with blue woven cloth in later years, don't know what it looks like in earlier years) that fits to a nipple on the bottom of the reservoir for the brake master cylinder. This hose is only pressure fitted to both the brake reservoir and master cylinder......not clamped, it's not under pressure so it doesn't need to be. If this hose is bad/leaking it would explain how the air got in the system in the first place and could account for the fluid leak you are seeing now. The fluid could also just be overflow from the reservoir from when you were pushing the slave rod back a few times. Check the hose very carefully and replace if necessary. To do so you most likely will need to take the master out, remove the hose from it, replace and run the new one up to the reservoir. One word of caution........the plastic nipple on the reservoir is not very strong, and the older it gets the more brittle it gets, it will easily break off if worked too hard getting the old hose off. I used a razor blade to gently cut the old one off when I replaced mine a year or two ago.
Old 11-30-2004, 06:18 PM
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ok i just encountered another problem, the clutch pedal is floored again.... after i had pumped the slave cylinder and got it completely on and i just previously had pressure in the master
Old 11-30-2004, 06:32 PM
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The master is pushed back by the pressure plate thru the release bearing and the slave cylinder. Look at the clutch arm and see if it has pushed the slave operating rod back into the cylinder, or if it is stuck in the released position. If the arm is in the operating (drive) position, try just pulling the clutch pedal slowly back up, then see if you have a normal pedal.
Old 12-01-2004, 09:41 AM
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Sounds like air is still in the system. Have you used a pressure bleeder to bleed the system yet? It is nearly impossibly to remove all the air bubbles without one.
Old 12-01-2004, 02:38 PM
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a pressure bleeder?? where do i get one?
Old 12-02-2004, 04:06 PM
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Performance products sells them for about $35.00. I believe 928 Specialists has them as well. Get one -- it's worth the small investment!
Old 12-02-2004, 04:28 PM
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I FIXED IT I FIXED IT!!!

ok maybe a little too dramatic but you gota understand that i'm 19 yr old college student with no prior experience with wrenching on cars

I feel great
Old 12-02-2004, 04:57 PM
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Glad you fixed it. Now, it would be nice for us to know what was the fix?? This thread is informative about the whole master/slave/booster set up but needs resolution.


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