After my wife and I got back from the 2019 West Coast Cruise I decided to tackle the squealing brakes we were experiencing on the drive. I finally finished the maintenance on what should have been a 1-2 job. Mostly a lack of time was the reason for the delay. Not getting all of the parts and the right parts cost me some time also.

The squeal had me thinking I needed new rotors and/or rear drums. It was difficult to determine exactly from where the noise was emanating. I took off the wheels, removed the front calipers and pads, took off the rear drums and pads, and inspected the drums and rotors. Rear drums were in good shape with plenty of material left on them. The same with the rear brake pads. Not surprised since the majority of the stopping power comes from the front. There was quite a bit of brake dust in the drums when I removed them. The rear brake cylinders were in good shape with no seepage. Front pads looked good as well but the rotors may have been turned a time or two (not by me) because they had a significant lip on the outer edge that you could definitively feel as you ran your finger from the centerline out to the edge. I opted for new rotors but forgot to order a new bearing kit with races.

While I had everything off I noticed a significant amount of brake fluid on the area under the master cylinder. Checked the fluid level and it was almost non-existent. I had topped it off before the trip so I knew I had a problem. Checked the area inside the driver's area by the brake pedal and the carpet was damp. Dang it, now I needed a new master cylinder. Out came the master cylinder.

While the drums were off the axle seals started to leak and dummy me didn't think it was because the 300 ft lbs of torque holding the drums on was not there which allowed some seepage. I bought a new axle seal kit and replaced both sides. Axles were still taking a couple days later. A call to P Downs confirmed my suspicions about the missing drums being the problem.

After I got all the parts I needed the rebuilding process began. Prior to putting it all together I used some 80 grit sandpaper and hand sanded the rear pads, front pads, and the inside lining of the brake drum to remove any glazing. In went the new m/c, assembled the new rotors with the new races and packed the new bearings with grease, installed the new rotors, refit the front calipers, torqued the rear axle nuts, secured them with new cotter tins, bent the pins to keep them in place, and started to bleed the brakes.

I picked up two quarts of Dot 3, located a 2 liter bottle, dug out some clear vinyl tubing from my parts bin, and made a catch for the old brake fluid. I had watched a number of videos on bleeding the brakes by myself but didn't want to chance it. My son came out to help with the pressure application on the pedal. Flushed the system completely of old fluid and air. Repeated the process on all four wheels. I forgot the front calipers had two bleeder valves and that caused me some anguish in trying to determine why the brake pedal was still soft after doing all four corners. Started to bleed it again starting with the right rear and made sure I did both bleeders on the front calipers. Adjusted the parking brake and put the wheels back on. It took a couple tries to get the pedal adjustment correct but eventually I could lock up all four tires without any pulling in any direction.

During all of this I replaced the exhaust manifold on my daughter's Saturn.

The only question I have for the more expert folks on the site is this;

When I bled the front calipers there are two bleeder valves. With the caliper installed in its normal position one valve is at the bottom of the caliper in a much lower position and the other valve is at the top of the caliper in a higher position. Should I have disconnected the caliper and laid it on the top of the rotor so the two bleeder valves would be at the same height when I bled them?


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RE bleeding, I've managed to have a fair share of experience. Especially in these little cars.

The top bleeders are all you need to worry about, air rises. On my front Wilwoods, there are bleeders on top and bottom, and I only bother with the tops.

I've had trouble getting the air out IF my pedal pumper is easy on the pedal. When we are almost done, as in almost all fluid and no air comes out of the bleeder, it is time to get aggressive. I have the pumper vigorously pump three times, then hold. Push rapidly, with high effort. You'd be amazed at the little tiny bubbles that come out. This gets ALL the air out, which is what you want.

I've tried vacuum bleeding, pressure bleeding, and IMHO plain old manual bleeding is the best way to go.

Yes, the bleeder needs to be the highest point to get all the air out!

On some brake kits the left caliper goes on the right and vice versa for proper bleeder orientation. Someday, Cory Drake will flip his calipers(so bleeding is a piece of cake), but the one with the L MUST be on the left in his mind LOL!

The calipers with 2 bleeders (one top and one bottom)  were done that way so they are no longer side specific and I'd imagine done this way for a reduction in manufacturing costs or inventory purposes.  Bleeder at the top is then you use.

Now, that said, when you get into Wildwood/Brembo/other calipers you'll have 2 bleeders, both on top, and in this instance they are for the front 1/2 of the caliper and the rear 1/2 of the caliper and both need bled.  Juts mention this so someone doesn't;t confuse having this type of caliper with 2 bleeders vs. having a "universal" caliper with 2 bleeders.

and I 2nd what Dany said, we have all kinds of fancy pressure and sucker bleeders and while they can be great for forcing fluid/air through a system, we always seem to revert back to the old pump, pump, pump, hold.... manual bleed method.

Thank you for the information guys. 

After I bled the lines initially the pedal seemed to be soft and I couldn't get the brakes to lock up at all so I questioned whether I got out all the air. The first time I adjusted the plunger arm on the brake pedal I was super cautious about making sure the pedal traveled a bit before it engaged so as to insure the plunger in the master cylinder fully expanded. However, I adjusted that actuator arm and the brake pedal still has a tiny bit of free travel but now the brakes seem more firm and the tires lock up. It does seem like the pedal travels a bit further than it did before. Maybe now with the pedal properly adjusted I'll bleed the brakes one last time. 

I re-read what I said last night and what I said about "don't believe...........   Well I meant this if the bleeder isn't the highest point.  Example: There are some GM trucks with dual wheel cylinders placed in a horizontal orientation. It is impossible to bleed the air out of either cylinder in that position. Similar as mentioned here. The backing plate had to be unbolted and rotated 90 deg to bleed them properly. The "flat-rate" method was to insert a piece of .002" feeler gauge down past the wheel cylinder cup creating a leak to allow total bleeding and remove it when finished.........Bruce

Michael B (aka bluespeedster SoCal) posted:

One step I had done to MC replacement was spend time to bleed the MC on the bench- that took some time. Once done, plugged all the ports before moving from the bench to the car. Then one  by one removed the plugs and connected the brake lines. That made the bleeding period super short.

I thought about that but opted against it. I didn't see how in the heck I would be able to get the brake lines attached before all of the brake fluid leaked out. After I installed the m/c I just pumped the brakes for a while until it filled. Then I loosened the brake line on the top which was for the right wheel and let air escape from there.Then I bled each of the brakes.

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