Brake bleeding and pedal height questions

[70STOVEBOLT]

I bought my master cylinder from Autozone, Duralast part number NM1494 here is a link:

https://www.autozone.com/brakes-and-.../49303_0_2558#

I used 1972 C10 for the application.

[rechinca]

So compare these two pics. This is the first booster I received and the one I just picked up. The first one that is installed right now and gave me a very low pedal height has a rod that extends approximately 3 3/8” from the rear of the booster. The second pic is the new one. This rod extends 4 5/8” from the rear of the booster. That should translate into the correct pedal height inside the cab. Due to rain today I didn’t get to replacing it, but should be done tomorrow. I think the years of guys complaining of this issue may have been caused by the same issue, an improper pushrod into the back of the booster.

[rechinca]

Well I took the other one out and sat this new to me reman’d unit in. Pedal height was much better! So I popped it out to clean and prep to paint it. For eff sakes there was a silver paint on the back hiding epoxy and around the studs and they appear to have been installed off kilter. The epoxy was gooped onto a bit of the threads and the base was not completely sealed. I have to tell you, whoever is doing this for NAPA (good chance for all the others too) is doing one half-baked job. It’s going back and probably going to source a new one this time. Can’t be any worse than what I am getting here. Used to be a guy could trust the blue and gold for quality parts. Their supplier is failing big time. Forgot to snap a photo so I’ll get that on Monday.

And BTW, LMC and Truck and Car Shop confirmed their MC’s that are listed as different numbers for Power and Manual brakes have deep pockets for the pushrod for what it’s worth. They couldn’t tell me anything about the calving or why the different numbers though.

[70STOVEBOLT]

When I converted my truck from manual to power (drum) brakes, I simply unbolted the master cylinder from the firewall and pulled it forward without disconnecting the brake lines, and bolted the used Bendix booster on and adjusted the pedal rod that came with the booster, and it worked fine. I have since converted to disc brakes and bought the master cylinder I posted above, using the same booster and it works fine.

[Andy4639]

I just installed all new stuff to me in my c20 ramp truck. I used the booster I had on the drums. I got the master from O-Reillys. Pictures show it plumbed into the truck. I did how ever just use a adjustable proportional valve though instead of the normal one. So far it is working great. The truck stops really good.

I installed a 1986 whole front end cradle in it. New upper control arms with new ball joints new pitman arm and idler arm. Pads and hoses.

[rechinca]

Originally Posted by 70STOVEBOLT

When I converted my truck from manual to power (drum) brakes, I simply unbolted the master cylinder from the firewall and pulled it forward without disconnecting the brake lines, and bolted the used Bendix booster on and adjusted the pedal rod that came with the booster, and it worked fine. I have since converted to disc brakes and bought the master cylinder I posted above, using the same booster and it works fine.

Stovebolt, thanks for the info. Can you do me a favor and take a measurement from the back of your booster to the middle of the eye on the pushrod and then one from the center of the pushrod to the firewall? Much appreciated.

[rechinca]

So I kept digging. Somehow I have not come across the website:

http://outintheshop.com/faq/Brakes/brakeinfo.html

scroll down to the bottom to the last couple of pics and it pretty much sums up my issue. I have a 3 3/8" pushrod and it says it should be 4 3/4". That should bring the pedal up a bit. Guess Monday we get to see what that new part looks like.

If you look close at the pic of the newest part, you can see the blobs of epoxy around the inner edges of all of the studs. Silliness.

[rechinca]

After two more horrible reman units, I was able to get what I hope to be a decent one. Ridiculous what is going on with them via NAPA. I have a Delco reman’d and as you can see from the pic, that push is a lot longer than first one. I
It also means that my pedal came up about the same 1.5”. So if you are having pedal height issues after converting/replacing a booster, check that pushrod from the booster to the swing arm.

Also solved the bleeding issue. I just cracked let them gravity bleed and added Russell speed bleeders. Much better now.

[BigBird05]

Not to highjack your thread but I just got a replacement booster ( for another brand ) and the front was installed 180 deg off.

[rechinca]

BigBird 10-15 years ago I’d have said no way. After the last 3 weeks, I have about given up on the reman industry. And to be honest, the guys at NAPA told me they really don’t care about the pet returned for a core, as long as they get the box back because that is more important and how they get their credit back.

[Peanut74]

Rechinca thanks for documenting your trials and final solution. I am about to head down this path myself. So as they say, "Better buckle up Buttecup its going to be a bumpy ride".