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This is a tough one.

The brakes were fair, but pedal travel too long, and not to my liking so I decided to change some components. Afterwards, I have not been able to build any pressure at all.

What I've done:

1. Changed master cylinder three times with different types, each time bench bled.
2. Replaced Booster with new.
3. Removed the shuttle valve from distribution block.
4. Removed the proportioning valve, installed T.
5. New bleeder screws, and yes Teflon taped.
6. Checked push rod multiple times. I adjust until there is pressure felt when bolting up the master, and then I back the rod off a couple of turns.
7. Inspected pedal to booster connection. Pedal is adjusted to proper height.
8. I've blocked off the calipers with a bolt to the brake lines to make sure it's not the calipers, and yes, they are on the right sides.
9. The brake lines are braided, NEW.
10. Inspected for leaks a lot.

For bleeding, I've used Speed bleeders, suction, and reverse pressure devices. Sometimes it appears there is no air, but other times there appears to be a little.

All of this and the pedal goes straight to the floor with only the booster acting as resistance.

What am I missing?

Last edited by rrs1
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Hi, just wondering if you solved your problem and what the cause of it was. I am experiencing something similar after having my front calipers rebuilt and fitting new brake hoses on the front, but not changing anything else - brakes were working fine before this change (except braking unevenly after pushing the pistons back to fit new brake pads - hence the caliper rebuild). I will need to intensify my bleeding procedure and see if it helps, but would like to know how you solved your problem.

cheers, Tim.

You cannot use a suction or reverse bleeder with speed bleeders. The speed bleeder has a built in check valve that only lets flow out of the caliper thus reverse bleeder does not work. The check ball has a spring that requires more force than vacuum to open it so vacuum does not work. You need to replace the shuttle as Marlin noted and then pump up the pedal until you get some resistance and then open a bleeder. You will need to do this numerous times to get the air out.

I feel your pain but the first thing that I would do is mount the master in the car and bleed it back to itself.

Regardless of the brand, I've had issues with brand new masters that when bled in the car back to themselves, solved the problem.

Why? Don't ask me to explain the inexplicable. In my experiences, what things are supposed to do out of the box, don't always.

If you get no pressure out of the master's ports then, it is what it is, the master is defective.

Last edited by panteradoug

My problem is solved and I have a good brake pedal now. I think there was an excess of assembly grease after the caliper rebuild which was restricting proper flow out of the bleeders, and also a bit of other 'crud' in one of them. So after removing them while using the pressure bleeder to 'blow' out the excess grease with brake fluid and giving them a quick clean, then screwing them back in, followed by rigorous bleeding, all is good. And the brake fluid now gushes out when I crack a bleeder open with the pressure on, rather than dribbling as before.

Cheers, Tim.

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