View Full Version : Front wheel cylinders (discs) -- any tricks?

05-31-2006, 08:57 AM
On my TR3, I had been seeing increasing amounts of fluid on the garage floor and this last time it was significant. It was clear fluid and the master cylinder reservoir level had dropped considerably. When I looked underneath I saw that the inside of the LF wheel was striped with wet streaks-- evidence of leaking for quite a while.
I had these rebuilt a year ago with new pads. I may redo these myself because I've lost confidence in the garage where I had this and starter work done. The manual I have does not have a good explanation or figures for the front cylinders and I wondered if there were any problems to watch for or tricks for making it easy (or avoiding mess ups) I started to pull it apart but the garage in question torqued the wheel nuts so tightly I couldn't get two of them loosened. I'm trying to decide to confront the garage owner again and have them do it or do it myself (after I get my breaker bar back from a neighbor).

Geo Hahn
05-31-2006, 09:59 AM
I had some lugs get way overtorqued beyond what I could easily loosen... stopped in the tire shop I always buy from and had them loosen them then retorque to something much more reasonable.

No special magic for renewing the rubber in the calipers. Inspect the pistons for pitting etc... stainless steel replacements are available.

Easiest way (IMO) to get the pistons out is to get them nearly ready to fall out using the brake pedal before undoing the caliper from the brake line.

If you use compressed air at any point (removing or refitting the pistons) keep your fingers out of the way.

Installing the piston with its new boot can be tricky -- I use gentle air pressure (with the opposite piston also in place) to inflate the boot against the piston I want to insert... then use a little tool made from a length of bare 12 ga copper wire (with the tip rounded and formed into a little hook) to help the lip of the boot get around the piston. First time may take a few minutes, by the 4th piston it pops on in 3 seconds.

Brake lube goo (available everywhere) will assist in the reassembly).

05-31-2006, 01:53 PM
yes geo is correct,
and definitely use brake assembly lube. usually what happens is the pistons corrode and ruin the seal. if you are keeping the car DEFINITLY install the stainless pistons. the cheap ones are chromed carbon steel. they corrode under the chrome then flake and cut the seals.

06-01-2006, 07:52 AM
Good input as usual guys.