Brake booster problem, Help

65sssd · Poncho Master!

Brake booster problem, Help

Beaumont4008 · Uber Guru

Just wondering is that with the brakes blead or with air in the lines?

Ghost Post · Poncho Master!

Is the problem vehicle the '65 Beaumont?.
And the pedal sinks by itself without depressing it?.
Are the drums on and the brakes wound up all the way?.

Here's a link to some booster basics that may be of some help..

http://www.autoshop101.com/forms/brake05.pdf

65sssd · Poncho Master!

The lines are blead and the pedal operates the brakes fine and is firm when the car is not running. Blead or not the adjusters should be fine. I adjusted them to drag ever so slightly when I put the drums on. I wish this was my first brake job but it's not and I can't explain it. I will check out the link.

67Poncho · Uber Guru

In my honest opinion, I believe there is something wrong with the diaphram inside the booster itself. Even if you had nothing for brakes, the booser still should not suck down and sort of tells me that the vacuum is making its way to the other side of the diaphram.
I remember a buddy and I put power brakes on is car and he would just have to breath on the pedel and it stop on a dime, NOW!!! We got another booster and all was fine.
Was it like it before if it had power brakes? Do you have another to swap with?? Even a good used one?

65sssd · Poncho Master!

That's the problem with 65 boosters, there hard to get in the right configuration. This is the third one. They all had the right part number but didn't fit. The rod to the pedal doesn't sit square so I'm going to disconnect it from the pedal and see if it does the same thing when I start it.

JerryA · Addicted!

You did move the rod to the other hole on the pedal when changing to power brakes, right??

mfleury · Poncho Master!

maybe push rod to long ???????

65sssd · Poncho Master!

The second hole, AHHH!!!! Hope that fixes it and I didn't wreck the booster. Thanks Jerry!

65sssd · Poncho Master!

I changed the hole and it doesn't suck to the floor but I'm not sure the booster is any good. The pedal goes down pretty easy but I'll have to get it rolling to make sure the brakes work right. Next is the clutch. I used the clutch out of project and it appears that it doesn't dis-engage the clutch when fully depressed. I took a risk with these parts and I might get burned. Any ideas?

Lemans64 · Poncho Master!

has this configuration been sitting for a while assembled?? Some times they rust together and won't release. usually the only way to get them apart is to push the car with clutch to floor or try and start it with clutch to floor.

JerryA · Addicted!

Glad that fixed that problem. One thing to watch on a swap to disc brakes is the master cylinder. From the factory they had a residual valving built into them for the rear drum brakes. Some of them now at the parts stores don't. I had the same problem when I swapped to front disc brakes. I installed a 5lb residual valve on the rear brake line. Cured the low pedal and they now work great.

Jerry

Also, did you bench bleed the master? I am not sure if this is a new drum to disc swap and it is a new master cylinder or not. You do have the master cylinder for a disc/drum setup right? You have a proportioning valve also, correct? Any booster from a A body should work.

65sssd wrote:

I changed the hole and it doesn't suck to the floor but I'm not sure the booster is any good. The pedal goes down pretty easy but I'll have to get it rolling to make sure the brakes work right. Next is the clutch. I used the clutch out of project and it appears that it doesn't dis-engage the clutch when fully depressed. I took a risk with these parts and I might get burned. Any ideas?

-- Edited by JerryA on Thursday 16th of April 2009 11:06:43 AM

65sssd · Poncho Master!

I went another way with this car. I left all the drums for originality, so the original tires fit, so the camber adjustment works, and went with a 68-72 power drum set up with a dual master. I blead the system before all of this but now that it is in the right hole the pedal doesn't drop but it seems pretty hard to push. I'll have to gage in on the road. As for the clutch that would be one hell of a ride. I live on a 300' hilly driveway.

-- Edited by 65sssd on Thursday 16th of April 2009 11:22:39 AM