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Brake issues

Cheapsunglasses

In Rust We Trust!
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I don’t even know how to title this because I’m completely clueless on what’s going on.

I have a 68 GTX, brand new brake booster, brand new dr diff aluminum master cylinder, all new braided steel lines, calipers have been on the car for 7 years but were brand new, factory proportion valve was removed and a brand new wilwood distribution/proportion valve installed.

The problem I have is the brakes don’t release. I’ve messed with the booster to master cylinder adjusting rod, and that doesn’t help. I removed the caliper thinking there was a problem with it, and no fluid came out of the line when I disconnected it, but there’s fluid in the caliper. When I press on the pedal fluid will come out of the line, but it doesn’t drip. I also took the caliper apart and there’s nothing wrong inside, all nice and clean inside.

Any help would be greatly appreciated
 
Was the brake system operational beforehand ? Is this a new system install ? What booster are you using ? Is it compatible with the dr diff mc ? I'm not familiar with a dr diff mc. What doesn't release, the pedal, or is the hydraulic system maintaining pressure ? Is it pressurizing the front ? the rear ? both ? did you adjust the proportioning valve ? Is the system bled properly ?
 
The brake system has never worked, which is why I’m so clueless on what could be going on. It’s all factory bendix style booster, and a body conversation kit from pirate Jack and it’s the front calipers that doesn’t release. The rears are fine.
 
ballast resistor.jpg


:poke::poke:
 
I was thinking residual check valve in the master and/or possibly having the m/c mixed up on routing. Disc doesn't require the rcv but drum does. Greg found out awhile back that he had the ports mixed up on the mc as who was who. When the brakes won't release, if you open the bleeder screw on a caliper when this is happening, does it squirt and then the rotor spins? Different matter but awhile back I had to replace the mc on the wagon as it was leaking out the back. It's a Doc Diff conversion pack so I emailed him to find out application. Never got a reply back so I winged it. 75- F-body[ aspen/volare] disc unit. 1 1/32". Got one from the Rock, no leaky now. And I did adjust the rod in the booster out.
 
This may seem overly simple but are you plumbed like so?

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I had an issue where I adjusted the booster pushrod too tight. I was aiming to cut down on the free play of the pedal and I went too far. The brakes reacted great but stayed engaged to some degree, making the brakes smoke! There are tools to measure the booster pushrod length but I've found it is easy enough to adjust, test and adjust until I get the right feel.
Money saved.
 
Yes, all the basics are checked like the lines being correct.

I’ve backed the adjuster off, but it still holds the brakes, and I loose pedal feel

I either get way to much pedal, or not enough, there’s not an in between
 
Can you send a pic of the front brakes, left or right w/ tire off?
 
If you crack the bleeder and it releases something is blocked or pinching the line. If its one side it may be the hose.
 
He’s got stainless braided front flex lines, so I’m pretty sure it’s not the lines. The OP bought a rebuild kit for the calipers and he sent me a pic, nothing wrong with the piston. Waiting to see what the passenger looks like. I mention to the OP that he should turn the air down to 5psi and blow the front lines out to make sure there’s no obstruction.
 
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