I recently replaced my front brakes with an SSBC kit to work with all new suspension components. I didn't touch the rear brakes outside of new pads and nothing else changed. The problem is that no matter how much we bleed the brakes the pedal goes to the floor. At first we thought the master cylinder was the issue it was making a sound like it was leaking air when you pushed the pedal so we replaced it. We bench bled it according to the included instructions, plugging both holes, putting fluid in it and using a screwdriver to push the valve every 15 seconds until it only moved an 1/8 inch. The pedal however still goes to the floor and now when the pedal comes up at there is a knocking sound from the master cylinder (like the vavle is slowly shutting then all of a sudden snaps shut). The brakes are all bled fine though, solid steam of fluid from each valve but the pedal will never get hard.

Any ideas? Is the master cylinder not correctly bled?

make sure you don't press ALL the way down when you are bleed brakes. You can rip the rubber seal on the master and let air in that way. It sounds like you have air in the master.

Just a thought......I once put new brake pads on my drum brake setup and did not adjust them out very far and I had these same symptoms.

The pads were put on the rears before I did the fronts and worked fine though. The ripped seal thing happened to the old master cylinder causing the sound, but as I said the new one still isn't working right and I'm getting that weird sound.

1. Rear disc brakes? If they're drums, you replaced "shoes" not "pads".

2. Bleeder screws at the TOP of the wheel cylinders? If the calipers are installed left-for-right, the bleeder screw won't be at the top, and there'll be a bunch of trapped air inside.

3. Any external leaks?

4. Is the master cylinder mounted at an angle, so the front is tipped "up"?

5. What method are you using to bleed the brakes?

6. Are you using low-drag front calipers but NOT using a quick-takeup (stepped-bore) master cylinder?

7. Do you see two little "geysers" in the master cylinder reservoir when your helper GENTLY presses the brake pedal?

8. Did you use the correct master cylinder for the booster? There are (at least) two different depths of pushrod seats in the master cylinder. A deep seat is used with a long booster pushrod; a shallow seat needs a short pushrod. If you used a deep-seat master with a booster having a short pushrod--the pedal will go way down without actually moving the master cylinder primary piston.

You verified that the brakes worked OK after replacing the rear shoes. Therefore, I'm guessing the problem is NOT in the rear.

If this were me, and everything else looked OK--I'd carefully pinch off the three brake hoses with needle-nose vice grips (rubber brake hoses only--don't do this with fancy steel-braided hoses!!! Pinch only enough to block the hose, you don't have to clamp it very tightly) and see if the pedal was suddenly hard. If it is, the problem is surely in the calipers. If not, the problem is most likely in the master cylinder.

I went to a place that specializes in brakes for the master cylinder, got whatever item number correspondes to power brakes front disc rear drum.

The bleeder screws on the fronts are at the bottom. You are saying they should always be at the top?

Master cylinder is at an angle, if anything more of an angle then before.

I don't know about the fronts being low drag, the kit including everything needed and didn't require a special master cylinder.

The cap was on when we were bleeding, if not the geysers would shoot fluid all over the place.

Correct, the rear brake shoes have nothing to do with the issue.

there are no rubber hoses on the front brakes, it's all hard line switching over to braided steal.

The bleeder screws on the fronts are at the bottom. You are saying they should always be at the top?
There's your problem. Calipers swapped left-for-right. Air rises to the top, you have HUGE pockets of air trapped in both of the calipers.

there are no rubber hoses on the front brakes, it's all hard line switching over to braided steal.
DON'T pinch them closed; DON'T bend them too sharply.

Which SSBC kit are you using? They have some with dual bleeders if the calipers have multiple pistons.

There's your problem. Calipers swapped left-for-right. Air rises to the top, you have HUGE pockets of air trapped in both of the calipers.


That did the trick, thanks! Gotta love when it's something so simple on all new parts, everything comes apart nice and easy and goes back together easily. Took all of 20 minutes, re-bled everything and it was ready to go. That was the last thing that needed to be "fixed" to get it on the road. Thanks for the quick replies.