View Full Version : I messed up the brake/clutch system


John (PA)
11-27-2005, 09:21 PM
I was very pressed for time doing a rotor/pad change. So I skipped opening the bleeder while compressing the piston to put the pads in. Other than that, routine change.

I drove the car for a brief time, seemed OK, parked it for a week, and left for vacation.

Tonight I jump in the car, go to push the clutch in and "THWACK" it pulls itself to the firewall floor very fast and stays there. Although full depressed, it did not actually move clutch disk. The pedal will not pull out to its normal position.

So, did I push the fluid into somewhere it shouldn't have gone when I squeezed the caliper? Unrelated? I'm not sure what my next step should be. My manual is on loan. :help

HansundFranz
11-28-2005, 12:37 AM
So I skipped opening the bleeder while compressing the piston to put the pads in.

I've replaced thousands of brake pads and have never opened a bleed screw to retract a piston. The next step should be to diagnose what is actually wrong with the clutch system, which is probably a leak at one of the hydraulic cylinders.

SStan
11-28-2005, 02:36 AM
Cold fluid leak, check under the clutch master cylinder and slave cylinder boots for fluid, whichever one is wet is the one that needs replace/rebuild.

Opening the bleeder before retracting a caliper piston is always recommended.
A. Calipers are the lowest and hottest part of the braking system, sediment and bad fluid form there first. Opening the bleeders gets rid of alot of the crap and lets fresher brake fluid down to the calipers.
B. Retracting the piston without opening bleeders forces the crappy brake fluid back up thru the ABS hydraulic unit, not a good thing.
C. Its a professional technician's "good practice".

thejlevie
11-28-2005, 02:55 AM
Opening the bleeder before retracting a caliper piston is always recommended.
A. Calipers are the lowest and hottest part of the braking system, sediment and bad fluid form there first. Opening the bleeders gets rid of alot of the crap and lets fresher brake fluid down to the calipers.
B. Retracting the piston without opening bleeders forces the crappy brake fluid back up thru the ABS hydraulic unit, not a good thing.
C. Its a professional technician's "good practice".
That's news to me... Opening the bleeder without pressure on the brake system from the master cylinder or reservoir (pressure bleeder) invites the ingestion of air. That's far worse than the risk of pushing old fluid back up the system. Besides, the brake system should be flushed no less often than every two years, which means that the shouldn't ever be any "crappy brake fluid" in the system

SStan
11-28-2005, 04:08 AM
I didnt say how its done, normally you would install a C clamp on the piston/caliper first and tension it before opening the bleeder.

Heres more info
http://www.ryderfleetproducts.com/cgi-bin/ryderfp/technicalbulletins/brakeabsprob.jsp

John (PA)
11-28-2005, 09:22 AM
OK.. I think you are on to something. I don't yet see a leak, but the fluid level was down really low. Since I can easily see the lines from the main fluid distribution block to the slave clutch, maybe it's leaking into the bell housing.



Cold fluid leak, check under the clutch master cylinder and slave cylinder boots for fluid, whichever one is wet is the one that needs replace/rebuild.

Opening the bleeder before retracting a caliper piston is always recommended.
A. Calipers are the lowest and hottest part of the braking system, sediment and bad fluid form there first. Opening the bleeders gets rid of alot of the crap and lets fresher brake fluid down to the calipers.
B. Retracting the piston without opening bleeders forces the crappy brake fluid back up thru the ABS hydraulic unit, not a good thing.
C. Its a professional technician's "good practice".

SStan
11-28-2005, 12:39 PM
Also look where the clutch pedal rod goes into the clutch master cylinder and check under the dust boot for fluid.

Once you fix it, an improvement is using a full synthetic brake fluid (DOT 5 or 6?) instead of regular brake fluid. Synthetic brake fluid has better lubricity and internal parts last longer. Ive done it to bikes, cars and medium trucks and had noticable improvement in hydraulic clutch parts life.