Wheels lock up.... brakes lock up.... what do I do??

[mysil bergsprekken]

Need some help on my 69 charger
When I hit the brakes, the wheels lock up and when I release the brake pedal it stays in.... I am able to put my toe in the back of the brake pedal, and pull towards me, then they will finally release, wonder what i should do, I bled the brakes but it was a no go...
I have the original brakes, drums all around and power brakes, (4 spd tranny if that makes a difference, compared to auto)

appeciates any help on this one??
Thanks

[blue69]

Check to see if the master cylinder push rod on the brake booster is adjusted to the correct length. If you have a service manual, if will give you the correct length.

[mysil bergsprekken]

thanks for the advice, yep thats a good point, one thing though, i have not pulled the booster or master cylinder apart, and it was working earlier, then it just got more and more stuck, is it possible thet the booster push rod will just adjust itself out of place?? perhaps. i don't know... what do you think?

[mysil bergsprekken]

but also one thing i was thinking, i gave it to a reply to "charger01" that it might be the brake pedal pivot, do i need to lubricate this often or what, is it anything that can wear out or something like that in the pivot??. since when I pull the pedal back with my toe the wheels slowly unlocks...

[blue69]

I don't think it can move by itself. Mine was still adjusted correctly when I took my master cylinder off. But if you want to check, it should be .910-.920" from the base of the master cylinder mounting studs.There are a pair of plastic bushings in the brake pedal pivot. You don't have to remove everything to inspect it. There are three bolts in the pivot link. Just remove the large bolt at the bottom.

[Steve P.]

Do you get the same results under all conditions?? Meaning, if you are sitting still? Engine off? Vacuum hose to the booster removed? Have you sprayed the swing and push rod bolts with lube? Try these things and let us know...

[mysil bergsprekken]

hey, thanks steve
how do I spray the swing and push rod bolts with lube? what lube to use? do I have do dissassemle the brake pedal and pivot from underneath the dash?

[Chryco Psycho]

get under the dash to lube the pivots , you have to remove the master to get to the pushrod though

[Steve P.]

get under the dash to lube the pivots , you have to remove the master to get to the pushrod though

Yup yup,, that about covers it...

[mysil bergsprekken]

I've got power brakes, I'm thinking to remove the brake booster if thats not too much hazzle and see if I can get to the pushrod.
What other possible reasons can be that my pedal won't return?
I'm anxious to get on the road
thaks for your replies by the way

[Steve P.]

Have you looked at the brake pedal assembly to make sure there is nothing binding. You need to fully inspect everything. Brakes are not something to be taken lightly. If you are not sure what you are doing with it I would get a knowledgable buddy to help or get it to a reputable mechanic..

[mysil bergsprekken]

hey do you know.
Where would be the best place to order a brake booster for my 69?
thanks

[mysil bergsprekken]

hmmm... I'm still stuck with that brake problem of mine, beeing away from home for half a year haven't helped me getting my charger on the road. I woinder if the brake booster has just gone bad, if its the check valve , the pushrod or something to do with the pedal pivot itself...
I am not quite sure how to grasp the situatioin. And would be thankful for any help. I want to get it fixed and my final last option I'd say, would be to buy a brand new brake booster and master cylinder assembly and see if that would do the trick.. but if the problem was lying in the pedal pivot thet probably wouldnt do me any good. Anyone have and idea??

[1BAD68]

I had that problem in my 70. You need a new booster, the diaphram actually works like a return spring where the rod runs through it but over time the rubber loses its rebound effect. I did a quick fix that worked for a whole summer until I changed the whole thing out... if you take off the master cylinder you'll see where thr rubber tapers down onto the pushrod, I slipped a spring over it to make up for the loss in the rubber and it worked well.
I also had the drums locking up but it was due to warped front drums.