That's what I was thinking. John, did your new master/booster come with a new acuator rod? If so, did you use it and was it the same length or different.
He had this problem before he changed the MC. Gotta be air in the system, somewhere.
I'm a hobbyist. Not a professional. Don't be hatin'!
Greg, give me a call and let me know of your travel plans. As always, we'll buy you a good meal if you come to town. 931-378-2060.
I went to a few websites this morning and many of them say a bad GM booster will, amongst other things, cause the pedal to go to the floor. There is an obvious, loud suction sound coming from the (booster?) when brakes are applied.
I replaced my booster a couple of years ago. It was one of the nastiest jobs I've had to do on the bird, as the 4 nuts holding the bracket to the firewall were totally seized. Nothing would free them up so I had to cut the old bracket/booster off and install 4 new bolts through the firewall.
Good luck!
Mark
68 Firebird 350 auto (sold) 70 Trans Am RAIII 400 4-speed (sold) 2011 Challenger SRT8 IE392 6-speed (sold) 2017 Challenger Hellcat 1966 Dodge Coronet 440
ANY sign of fluid getting past the wheel cylinder seals is unaceptable. Not to mention unsafe. If you see any sign of leakage it is time to replace the cylinder. If it were mine I would do all of them, if they are near the same age.
Did i miss a post? 69verts correct. Absolutly no fluid leak!
Don't know if you missed a post or not. Just seems that if air is entering the system, then fluid should also be leaking out. Just exploring all possibilities...to get Jon back on the road.
I'm a hobbyist. Not a professional. Don't be hatin'!
I have scrounged up all new hardware (cylinders, pads, springs and related hardware) and have an appointment tomorrow with a local Brake specialist. Will let you all know how this goes.
'68 428 HO M3 Monster, 4-on-the-floor! Need I say more?
There could be a signifigant problem with your game plan. These system are so obsolete that you will be lucky to find someone who has a remote clue how to do these kind of brakes. They are simple, but you have to understand them. It's kinda like removing the window crank clip, an easy process if you understand what your are doing.
Gus, I am the tall dark-haired guy in the videos...the one that thinks he's in charge!
Merv, you are right, but the Brake guy owns a 1968 Camaro and did my alignment last year. All he does is brakes and alignment. Otherwise I would not take the bird to him.
He fixed the brakes today, in about 65 minutes! Replaced the two front wheel cylinders, professionally bled the system, and adjusted all four brake assemblies. I'm sure he did a few other things. Brakes are stronger than ever now, plus he properly adjusted my parking brake, which has never been 100 percent right.
Thanks for all the help gang; I learned alot on this subject.
'68 428 HO M3 Monster, 4-on-the-floor! Need I say more?
Yuppers, looks like it was a combo of things. Leaking M/C with front leaking wheel cylinders and possibly a booster, but good to change regardless. Gotta always remember to pull back the outer boot on the wheel cylinders to check for leaks when your looking at them.
bump,bringing this thread back up as i started my bird the other day for the first time this year and the pedal went to the floor with the same vacuum sound John had.I took the booster off and am going to order a new one (3 yrs old) but after reading this i'm wondering if i need a master cylinder too! (don't know how old it is)
some more info -4 wheel drum,wheel cylinders are dry.master cylinder is full,don't see any leaks.so what you think replace booster first and then if no change replace MC or replace them both ?
![[Linked Image from hosting.photobucket.com]](https://hosting.photobucket.com/albums/ss328/alvey_john/john-alvey-1968-Firebird-oct2012-2.jpg)
