Hey all, hoping someone here can tell me what's going on.

I bled my brakes this past weekend and thought I followed the correct procedures, but the pedal is still incredibly soft although the car does stop eventually so I am getting some brake pressure, just hardly any. I bled the master cylinder, then the fronts, then the inner rears, and then the outer rears. I know for a fact that the booster is new, and I'm almost positive that I replaced the master cylinder at the same time. During the bleeding process, I never let the master cylinder go dry and no air entered the system there or from the pedal being released. I am also getting pure fluid with no air out of each of the bleeder screws.

Any help would be appreciated!

 

Is the M/C pin to booster length correct?

 

Is this something that would've been set at the factory? I'm almost sure the booster/cylinder assembly was one piece when I installed it, so shouldn't that have already been done? Regardless I will check it. Thank you!

 

Yes. If you bought a MC / Booster combo, I would think that the measurement was checked. No need to tear that apart. The problem with that combo however, if it was installed as a one piece unit then its not likely it was bench bled. Then you will have a bubble or two trapped in the MC.

Your caliper bleeding procedure is a bit unusual. Farthest from the MC goes first, then work your way to the front.

A brake pedal to the floor is a leak.
A soft brake pedal that does not go to the floor is air in the system.

 

Did you also bleed the MC while on the car. Try this. Works great everytime.

https://www.corvetteforum.com/forums...-cylinder.html

 

Very helpful! Thanks for posting.

 

I have taken this advice in the past, it works.
Eddy

 

In addition to the caliper order that HeadsU.P. mentioned, tapping on the calipers and junctions may help free air bubbles.

I bough a pair of these brake catch bottles, so I can do both sides of a rear caliper at a time.

Are you using a pressure bleeder? I don't think it maters in that case, but if you are not, air can get in around the bleed valve threads. Even using the pressure bleeder, I used a dab of Loctite to seal the threads (the actual seal is the tapered seat, so, don't get goop on that).

 

Is the brake warning light lit on the dash? Yes? Follow step at the end. Is the pedal rock hard after a few pumps with the car off? If not bad booster. I would bench bleed the master in a vice before going any further. Rap it with a rubber mallet while in the vice to be sure no air bubbles exist in the piston. Set the booster pin with the tool as "Peterbuilt" suggests. Install the master to the booster on the car. Use the motive power bleeder to bleed the system. Do not exceed more than 15 PSI on the system. Don't use the pedal to bleed. Do one caliper at a time. Standing at the back of the car looking forward. Bleed Front Left -- > Front Right --> Rear Right Inner --> Rear Right Outer --> Rear Left Inner -- > Rear Left Outer. I would suggest rapping the calipers while the bleeder is open to ensure there are zero air bubbles. Air in the system will equal a low and or spongy pedal. After completion if the brake warning light is on at this point press brake down slow and firmly. A click should be heard and the light should go off. You can pressure bleed the system twice if it makes you happy before disconnecting the motive system.

I fought with this brake system for months and this is the only way I was able to rectify the problem.

 

Thank you, everyone, for the helpful answers. Looks like I've got a few things to try, thank you!

 

 

Don't forget there are 2 bleeders each on the rears: 1 inner and 1 outer on each side