WBYonder

I had replaced a seal on one of my brake calipers last week and in my haste to get the car back on the road, had left the brakes a bit softer than normal, so I started by bleeding the brakes this afternoon.

I had only taken one caliper off to replace one seal. I'm not sure how the seal got damaged. It may have been defective, but more likely I installed it twisted or perhaps let a piece of grit in there when I reassembled the calipers after powdercoating them last spring. No problems until a month or so ago when I noticed a leak at the right rear wheel. Brake fluid. I took the pads out and saw that only one cylinder was leaking (the larger one). Called Sunset, got the rebuild kit (as always, great service & prices). Pulled the caliper off, took one cylinder out and saw, with relief, that it was definitely the seal (as opposed to a scored cylinder)



The bad seal is on top, damage at 9 o'clock.

Anyway, got the caliper back together, mounted, bled that caliper and buttoned everything back up. Brake was soft until about 1/3 way down, but did not have the time to bleed again and get the air out, so waited until this weekend. I wasn't sure if I needed to just bleed the one caliper, but I figured I probably should bleed them all anyway, to be safe. Got that all done and figured I had plenty of brake fluid and I should bleed the clutch slave cylinder too ( I wussed out and didn't do that in the spring when I did the brakes). Plenty of afternoon left too!

So, I looked it up on RL and found the bleed nipple. Kind of a bugger to get to get to. I loosened the the nipple with a 7mm box wrench, repositioned the wrench for more travel and attached the tubing to the nipple. I found that by setting it up this way, I could take an extendable magnetic retriever and move the wrench up to start the flow out of the nipple. When I wanted the flow to stop, I let gravity drop the wrench back down (righty tighty!). That way I didn't have to get my arm in there and risk knocking the hose off. I got some nasty dark fluid out of there and some crud bits as well. I got some bubbles out, which I thought was strange. I had fluid in the brake reservoir, but I added more anyway. That seemed to stop the bubbles and the fluid coming out looked good, so I closed that up, got the tray back on, wheels back on and the car off the jack stands. Got in and stepped on the brake pedal. Sweet! just like it should be. Stepped on the clutch, and crap! The pedal stayed on the floor! Back to RL, 993 search: clutch pedal floor. Ahhh, must be air in there. Tried pumping the pedal a bunch of times, as some said they had done. Didn't seem to be getting me anywhere, so I figured I'd best get the car back up in the air and bleed the air out. I figured the slave cylindeer could use some more flushing anyway after the junk I had seen come out of there. This time, I put the brake fluid in the Motive bleeder (I wasn't about to pump air back in there again) and flushed some more air and crud out. Got steady fluid coming out for a good stretch, so I tightened it back up and tried the clutch. Success! Checked the brakes, just to be sure... still great! Buttoned everything back up. Took a quick run on the road to confirm everything worked well and it did. Life is good!

IXLR8

How did you install the piston? By hand (finger pressure) or with a C-clamp?

WBYonder

Both times, when I first rebuilt the calipers and when I replaced the one piston, I installed it with finger pressure.

To pop the piston out to replace it, I took the pad out on the side where the bad seal was (outside) and put a little block of wood in where the brake pad was, for the piston that I wanted to leave in place. This left nothing to prevent the one leaky piston from popping out. I then stepped on the brake and the piston came out, no problem.

nathan1

Rob- I need to in invite myself over for beers, it sounds like you are truly bored! The 993's can hang out and the adults can drink some Manny's!

P-daddy

Nice, thanks for sharing. So many good threads on caliper rebuild/powder coating lately, I'm still a little too chicken to tackle something like this. I felt this way about doing plugs too, but did it and wasn't bad at all.

WBYonder

You're welcome anytime Nathan! When are you moving into the neighborhood?

WBYonder

I'd say go for it. It wasn't difficult and I was really pleased with how they came out. The red brakes on your car would be a natural, and nothing beats the satisfaction of doing it yourself. There's plenty of guidance on RL too.