Brake Help

[roadking77]

If anyone has a stock disc brake settup from 79, is it possible to post some pics of the caliper and in particular the line feeding into the caliper.

I am having a devil of a time getting my rear brakes hooked up. I bought calipers from Firebird Central and after talking with them found out they are for someone doing a conversion to disc brakes. I have hard lines installed which I thought were exact reproductions, I may have bought them from inline tube? The hard lines I have do not fit into the Caliper. The Caliper I have is made to accept a banjo bolt not a flare nut fitting that I have. I have tried getting parts to marry the two together but so far no luck. I found something close from JEGS, an inverted flare female fitting but the threading is off. I called and what I got from them is the closest thing they have.

Looking in my 1979 Service Supplement Manual I see nothing in reference to the 'feed' line other than a note that says
"if brass bolt and block were removed..."  Looking at Tom's thread about a parking brake I can see in the pic what I think is the brass block.

SO, I am looking for ideas, or if someone has an original pair of calipers that can be rebuilt that they want to part with.

[tinpusher]

I’ll check my 79 tomorrow ….been awhile since I did those.

[tinpusher]

Drivers side:

[tinpusher]

Passenger side:

[tinpusher]

Pretty close to stock if I remember right. Swapped out those brake lines about 10 years ago and the stock ones also had the excessive bends prior to the caliper for the side to side movement

[roadking77]

PERFECT!!  Thanks so much. The last pic shows pretty clear the 'block' that the line feeds into. The 'block' appears to be installed with a banjo bolt. That is the part I have been having a problem with. That block thingy is creating more problems for me than should be allowed. I see I dont really need new calipers, just that termination block. A couple of people have been telling me that the rear used a flex line similar to the front which I had my doubts. Thanks for confirming. I have the same lines on my rear that are new but supposed to be good repro's, which they appear to be.

[tinpusher]

No problem, I think that banjo bolt has a pretty decent shoulder to it… Good luck.

[roadking77]

After much digging yesterday I found my original calipers. Was able to salvage the brass block and using a new bolt and washers got things hooked up. Now to get the system bled!

Thanks again for your help, it was greatly appreciated.

[glhx]

I have this system and I have had a very hard time getting it bled. The fronts bleed fine.
The back passenger side as well.

The drivers side keeps pulling in air and I think it’s pulling it into the caliper from the parking brake system.

If you can get this bled. Please post and let me know what you did and where you got your parts from.

My whole system is all new. All the hoses, brake lines, calipers and master are new

[roadking77]

I am having the same issue actually. I have a 'mighty vac' hand pump that I used on the fronts and it worked like a charm. I got the rear caliper hooked up and started with the mighty vac last night and I pumped until I couldnt stand it any longer. After letting it sit a bit I found a leak where the main hard line attaches to the flex line that leads to the splitter on the rear. I have a very clean shop floor and saw a drop of fluid. I tightened that up and pumped some more but no luck. I figure I at least have fluid to that point in the system. I am going to get help today on the brake pedal and try it that way. If that doesnt work I am planning on going back over the system.

When the shop did my 77 the mechanic told me he could not get the rears bled and found out it was a bad master cylinder?
He swapped it out and solved the problem.

[glhx]

 Mine isn’t leaking fluid. It’s pulling in air.
What I did was several things

First I used a pressure bleeder. This didn’t help
Then I bled them with help of a person…..the normal way. It didn’t help

Then I hooked 8’ of 3/16” tubing to the bleeder screw and ram it all the way up to the master cylinder to cycle the fluid. Like bench bleeding but on the whole car. I sealed the threads with Teflon tape for the bleed only. Then cracked the screw and left it open. 200 pumps later and it still pulled in air.

To rule out the Teflon tape being the problem. I drilled a bleed screw down the center so it could be tightened down all the way but still flow fluid. Still hooked to the 3/16 tubing to the master cylinder and cycling. 200+ pumps later it’s still pulling air.

So then I got a second person. Went back to the original bleed screw and hooked back up the 3/16 tubing back to the master cylinder.
I don’t see why the fluid needs to go into a bottle when it can just go back to the master cylinder.
Bled the natural way…..
3 pumps and crack the bleed screw.
This showed me.

For sure that somewhere in the drivers side back caliper or the lines in between are pulling in air.
It’s timed air.
I pump it up 3 times and crack the screw. No air.
Pump it again and crack the screw. Same amount of air every other time and it cycles like this.
3 times….no air……3 more times…..air…….3 more times…..no air

My next step is to take apart the caliper and look for putting in the seal area.
And remove the brake line and re seat it.

Other than that…….it has been a long expensive problem.

The whole system is all new. I’ve replace everything.

I will add that bleeding this way with the hose from caliper to the master cylinder. With this type of caliper will allow you to pump the Brakes as many times as you want with no mess and it will get all the air out of the system. If there is no leak.

I’m 100% sure I’m pulling air in the drivers side system.

I’m hoping you have better luck.
These are calipers from oreilly but they are cardone rebuilds

I have solid knowledge of the system. Especially how to set the e brake and how the caliper works internally.

I have some old calipers taken apart showing the whole thing.
I have a good idea which seal is leaking and im pretty sure it’s the e brake seal.

The yellow thing in the center is typically not a leak point. There is a large o ring in the piston itself that should seal all of that. It’s buried way down inside the piston ratcheting system.

[5th T/A]

Several people have problems here, so my 2 cents worth with some suggestions. While vacuum bleeding can work I was never a big fan. You can only draw 30” of Mercury with Vacuum. Working pressure on a hydraulic brake system is probably 1000 PSI, maybe more. Meaning the lines and fittings are probably rated to withstand many times that, like 3000-4000PSI. Meaning brake fluid that can not compress should show any leak better than a vacuum. As far as how many brake pedal pumps to successfully bled a system, it should never take a hundred. Usually anywhere from 1-2 quarts of fluid. I never recirculate the fluid because it could be contaminated. I never use brake fluid from an open container because once open it will absorb  moisture.

To start I would have one of the bleeders open on a rear caliper and have a helper slowly pump the brake pedal. At this point no need to close the bleeder screw every time the pedal is down as you are just trying to get fluid to the back of the car. Once the fluid starts spurting, close the bleeder screw when the brake pedal is down, do not release the pedal until the bleeder is closed. Then the helper in the car should pump the pedal several times, while they are holding down the pedal, crack open the screw and tighten bleeder before repeating the process. Eventually the pedal should get higher and harder as all the air is bled out. I usually put a plastic hose on the end of the bleeder screw running to a jar to avoid getting brake fluid on car parts as it will remove paint and makes less of a mess. Cover fender near the master to protect paint from any spilled or splashed fluid. While bleeding the master cylinder cover should be in place to avoid splashing. At the same time the fluid should never get to the bottom of the reservoir or you will induce air into the master.

Assuming you don’t get a firm pedal and it’s not obvious where you have a leak. You can  eliminate components such as calipers, lines, fittings, proportioning valve. You can use an inverted flare nut to cap the circuit, weld it shut or try epoxy to create a plug. For male end you could use an inverted flare union. Starting at the rubber hose and T on the rear axel. If that doesn’t give you a firm pedal you could disconnect the line from the rear brake line to the proportioning valve and put the plug in there. Keep in mind when you are putting this plug in you would treat it as a bleeder screw and still have to bleed the circuit. But this should allow you to isolate the problem.

[tinpusher]

Maybe pull the MC off the booster enough to check for dampness/leak without disconnecting the lines. I would try a gravity bleed then button it up and test it. Hold that pedal down for a few minutes then check for leaks.

I’m also posting the same info on the other post with glhx