Brake Booster Question

[67 442]

The brakes on my 67 442 are a little lower than normal this year. The pedal has always been low for my taste but this is a low milage car so I just accept it as normal for this car. I have replaced the whole brake system except for the booster in the last year. My question what happens or what does the brake pedal feel like when the booster is not working? Does the pedal become lower or what might cause the pedal to be low?

[StriperSS]

Is the pedal just low, or only when you press the brakes?

[m22mike]

Check the rear brake adjustment first, More piston travel ='s more pedal travel.
Mike

[budnate]

make sure the drums are adjusted properly, most people dont and run them waaaay to loose.

[67 442]

The pedal travels about six inches then about 1 1/2 " from the floor I get a firm pedal. I have adjusted all 4 drums with a brake caliper so they aren't loose or too tight. I was thinking last night after I posted this that I might need to look at the rod for the M/C and see if I can modify that to bring the pedal up a bit.

[jl8z28]

I have seen rods for the M/c different lengths

[PeteLeathersac]

Some m/c rods are a threaded/adjustable style too..
If so, make sure you know where it was so you can return to the same setting when you find the real problem..

Have you been adjusting the brakes w/ the tool through the backing plates?.
As long as there's no wear inside the drum edge, it's sometimes better to wind the adjusters fully by hand so you can barely twist and slip the drums on and see how that works..

Have you applied the brakes w/ the wheels in the air and someone else trying to turn them to make sure all are grabbing?.
Occasionally there's air still trapped somewhere in the system you need to bleed out before pedal will go high..
Elevating the end of the car that needs bleeding sometimes helps..
If the stream is weak, the old school trick was smacking the master w/ a hammer while pumping/bleeding itself to release any air trapped in it then bleeding the wheel cyls after that..

Good luck!.

~ Pete

[budnate]

It sounds like you have air in the system yet, and not to sound cocky, adjusting the drums on the car with the wheels bolted on tight is the only way i have ever seen it done and adjusted so they truely are tight so you get the slight chew chew sound of the shoes dragging on the drum ... anytime there adjusted where you can slide the drums on and off easy and mic them there to loose.

[67 442]

All very good suggestions. I'm going to run thru everyone this weekend. I use a vacuum bleeder so I can do it myself no pump 5 times then hold anymore. The more I think about it the more I think the M/C rod is not pushing enough fluid down to the wheel cyls.

[PeteLeathersac]

The idea of adjusting as high as possible then slipping the drums on was to confirm the brakes were actually wound up and something goofy wasn't happening like the adjusters being reversed causing an unwind when adjusting by hand or by the auto adjust when in use?.
If they're wound up to where you can just get the drums on they'd be high enough to give a real pedal and discount the actual adjustment as the problem..

~ Pete