69 power brake booster clearance

[Brad S.]

I'm trying to install brake booster clevis to pedal and am having to pull up on pedal ( into rubber stop) to get the pin in. Which means I have "negative " clearance. I would think this would cause the brakes to start to be applied. Should there be clearance at the clevis connection? If so how much? The rubber stop is new so I'm thinking the stop thickness might not be exactly right causing the pedal to be slightly to low.. Any suggestions? Thanks Brad

[Bill C.]

Re: 69 power brake booster clearance

Brad,
Have you just converted to P/B set up?

If so, the booster clevis attaches lower on the pedal in the hole where the std brake set up switch actuator is mounted. Remove it. You will also need to purchase a P/B set up switch actuator and mount it in the upper hole using the bolt from the latter. The two actuators for the switch are not interchangeable.

Bill

[Brad S.]

Re: 69 power brake booster clearance

Bill , the car came from the factory with power brakes and am using the original booster and pedals.

[Bill C.]

Re: 69 power brake booster clearance

Is the booster a replacement?

Is the clevis threaded all the way down against the stop?

[Brad S.]

Re: 69 power brake booster clearance

Bill, the booster i s the original that has been rebuilt and the clevis is threaded all the way against the stop. The pedal shaft bushings and the return spring have been replaced. Thats why I'm thinking that the rubber stop (Dr. rebuild) is a little to thick not allowing the pedal to return enough. thats all I can figure out.

[Bill C.]

Re: 69 power brake booster clearance

Can you compare the new rubber stop to the old one?

Sounds as you may have a stop thats too thick, as you suspect.
Can you trim it ?

[Brad S.]

Re: 69 power brake booster clearance

Bill, I used a belt sander to take about .015 off the bumper and it helped. The only way to get the bumper out is to remove the pedal assembly. the dash is not in the car which makes it ALOT easier. I need to take some more off so the pin fits with no interference and then give it a little clearance. The AIM says that the master cylinder Should have between .06 and .250 clearance. It doesn't say anything about the booster How much clearance should the booster have. I would think it wouldn't need very much.