So on our 67 442 we have a completely new brake system all the way from the master all the way back to the drums. I have put about almost a gallon of fluid through all four corners and have seemed to have gotten all the air out with my pressure bleeder and by foot. I can not seem to get a good pedal. I have checked the push rod to master clearance and is it within limits. I just cant seem to get a good pedal. It will BARELY stop under its own power.


Yes I did bench bleed the master before installing it.

 

At this point I would think you have a defective master cylinder. If you bench bled the master prior as you mentioned, as long as you kept filling the master before pumping it dry to fill the lines you should have been ok. You may want to try to bleed the whole system again. Did you replace all the junctions as well ? No visible leaks around the caliper or wheel cylinders or junctions? Is the brake light still on ?
Eric

 

Yeah every single part in the entire brake system is new. Master, pro valve, lines, hose, calipers, cylinders etc. I may try and get a new master. The one the kit came with was one of the polished units with the screw on caps. I hate it. No visible leaks. Im going to try and bleed it one more time. I just really hate taking the tires off because it has crager classics on it and I hate the lug centric wheels. Cant wait till the new wheels and tires are ordered! haha

 

Do you get a firm pedal while pumping prior to opening a bleeder?

 

Not really. Im going to go down tomorrow and pick up a new master. Its only $32.

 

I would just call the outfit we got the conversion kit from but I HATE those guys and will never call or buy a single part from them EVER again. So im just going to buy another one.

 

As long as you didn't pump the master dry while filling all the lines and installed the plunger back into the booster then I would say it's the master.

 

Yeah she never dried. haha I have made that mistake before. haha

 

Cool I hope you get 'r fixed .
Cheers
Eric

 

What is your system, drum or drum disc or disc?

 

It's now disc drum.

 

I am having some difficulty as well with a factory front disc system on my 67 TC. Everything new including factory style prop valve repro. Just regular bleeding I could not get fluid out of rear wheel cyls. Finally I back fed fluid up and with prop valve the wheel cyls would only spurt a tiny bit of fluid. I tried another master and the same result so I am still trying to figure out what is going on. I may need to use an adjustable prop valve...

 

Does your prop valve have the little pin in the front of it? Cause I did some research and if your not getting fluid to the rear that pin in the prop valve (which is the metering valve) may not be centering and blocking fluid to the rear.

 

Yes the pin is behind a rubber boot on the rear of the prop valve, I am going to try pressure bleed as well.

 

Have you tried reseting the pin?

 

Ya it doesnt reset, it appears to be spring loaded, it just pushes in a bit and then comes out. I had a clamp on it when bleeding like the service manual shows...

 

Hmm mine pushes in pretty far. I wonder if you may also have a bad master as well. I got my new master on some cardboard with the first coat of raw cast iron paint on it right now. Don't want it to rust.

 

If you still have trouble after replacing the MC, here are a couple of thoughts:


- Are the disc calipers installed with the bleeder screws on the top side? If not they won't bleed.


- Remove the bleeder screws, put some SILICONE grease on the threads and reinstall, then bleed. This saved me one time when nothing else worked, symptom of Chineseium...

 

I will be installing the MC tomorrow hopefully. I have big hopes. The calipers are installed correctly haha. What did the grease do for you on the bleeders?

 

Don R, do you put the grease ion the threads to prevent leakage through the threads? In the past I have sometimes wondered if I am getting air through the threads, especially if using a Mity Vac.

 

So got the new master on today and wow does it look better then that BS chrome one. Still haven't bled it yet I will do that tomorrow.

20141226_161330_zpswnhzihbw.jpg
20150227_165150_zpsnj4puls3.jpg

 

I do like the look of the chrome one, I know they say chrome will never get you home, your engine bay looks great both ways.
I hope the new master takes care of the problem.
Cheers
Eric

 

Haha I just didn't think it matched the other thing under the hood. Yeah I'm hoping to have a great pedal by this afternoon.

 

That is correct.

 

Then you are wasting your time.
If air can get into the system via bleed screw threads then brake fluid can get out.
What grease will do is stop the thread seizing up through corrosion.
The taper on the end of the bleed screw makes the seal. It only needs to be tighten firmly, overtightening it may cause grief when you come to undo it at a later date.

Roger.

 

So with minimal spillage I got the new master in and bled. She now has the pedal of a new car. I feel much better now. One more thing marked complete on the very long list of things.

 

Idk maybe.

 

Ok so now I have two problems. First it doesn't seem to have power brakes. I'm going to check vacuum at the booster and see what I have. The other issue is that the front brakes will not release. I'm running stainless braided lines front and back. Brand new calipers. I'm thinking maybe the pro valve. What do you guys think?

 

Double check to see if all is plumbed right, lines from master to prop valve and all... this crap happens a lot it seems with new parts and keeps you guessing as to wether new parts are good.

 

Also check the adjust ment of your master cylinder pushrod - if there is even the slightest preload on the M/C piston from the pushrod, your front brakes will not release.

- Eric

 

Ok yeah that was going to be my first thing to look at. I know it's plumbed right because all the preformed brake lines only go on one way.

 

What's the proper rod adjustment?

 

I don't remember the number, but it should be in the Chassis Service Manual,
The bottom line is that there has to be several thousandths of play before the rod contacts the piston.

- Eric

 

Yeah that's what I was thinking. I will look into it next week cause I'm about to go out of town for the week. This is going to be eating all week haha.

 

You could just loosen the screws that hold the M/C to the booster and stick a few washers between the master and the booster, retighten and try it - if the problem goes away, you know that's it, and can do it correctly when you get back.

- Eric

 

That a good idea

 

Yeah, it's brutal but effective. When I was a kid, I had a car where I just wasn't in the mood to screw around under the dashboard; I figured the exact right number of washers, and drove it around like that for months.

- Eric

 

So I got the pedal rod adjusted and the dang brakes are still hanging up. My next step is to disconnect tye master from the booster and see what happens. Here we go

 

Just a thought, those callipers could have been sitting on the shelf for months, You may want to see if the piston is moving feely in the calliper. You could always use an air nozzell to blow the piston out of the calliper and lube up the " O' ring some and reinstall.

Eric

 

So good news. The non adjustable booster rod was sticking to far out. I unbolted the master and she rolled with easy (well as easily as a 67 A body will roll haha) so I put one washer (which actually was the same color as the booster so you can't tell) behind the master and it works great so far. I also got my power brakes back. I have t pulled it out of the garage and drove it around the block to see how it works but sstatically in the garage seems to work great.

On a different note I take it in on Monday to have the vinyl top put on. I can't wait to see it with the top on.

Thanks guys for your help.

Kyle