Bleeding Brakes... Help!

OK so my SC is getting work done right now, new brakes/rotors, new rear calipers, and now it is time to bleed the brakes... I have a leak somewhere that we cannot find right away, but I also made a (stupid) mistake of refilling the master cylinder with about 16 oz. of Power Steering fluid, which all drained onto the floor of my garage in about 5 days. Now, I was wondering if this would cause any seals to swell (I hear P.S. fluid is thinker than brake fluid), and we are having a problem bleeding the right rear brake, where there was a new caliper/rotor/pad put on.... Could the power steering fluid have caused a problem anywhere in the brake system? PLease help, I want my baby back on the road.

Rubber parts will start to swell within a couple of hours after being exposed to power steering fluid.
Did you bleed your brakes with power steering fluid in your reservoir?

Well, no. What happened was I added more brake fluid, roughly 40 oz. of it within two bottles, and at first it leaked right out, then later on when the car had been sitting for a few days, I added more and it didnt come out anywhere. I would assume that all of he power steering fluid is out of the reservoir, plus I believe the front brakes are bled, yet the rear are giving problems still.

If it were me i would purge the whole brake system!! start with the passenger side rear and just keep pumping fliud through it. Brake fluid is fairly cheap, so don't take any chances. Bill...

Yeah, from what I hear the mechanic tried air-bleeding them, but couldnt get the rear driver's side to go through. Now when I took it home, the brakes where fine until i got about a mile from my house when the ABS and Brake light came on, then the Check Engine light came on when I hit a red light. When I got home and popped the hood, I found a hole in the flimsy black hose that is around the master cylinder, and brake fluid was running down to the Cat below. Now... the mechanic told me he fixed the rear pass. caliper which was leaking, but it was still leaking around the proportioning valve where I originally saw it leaking but it didn't leak when we were checking it out. I have a theory that the power steering fluid may have swelled the proportioning valve to the point where the left rear caliper may not be bleeding, and the brake fluid is backing up and leaking at the proportioning valve and also the black hose. What do you think?

The procedure to bleed the back brakes is different than the front. You need to have the ignition on to do the back brakes.

How are you doing it?

I didn't know about the ignition part, but as far as I know the mechanic was doing the back brakes the same as the front. My uncle is a good mechanic and he's gonna take a look at it, I'll have to let him know about that. He mentioned something called "gravity bleeding" where you just open the line and tilt the car and just let it open til everything comes out.

The proper way to bleed the rear brakes is with the ignition set to the ON position and then pumping the brakes to bleed them. Other conventional ways WILL NOT work with these back brakes.

Remember to get a small piece of rubber hose to put on the bleeder screw as the fluid in the rear calipers is under high pressure and shoots out when you bleed them.

So just tell the mechanic to turn the ignition to ON when he's bleeding the rears and he'll have no problems.

Steve

Hey thanks a lot man, I'll give that bit of advice to him when I get the car back over there.