63 drum brakes pulling

[Boyan B.]

Re: 63 drum brakes pulling

I dont beleive the cylinders are stuck since I get full locked brakes on both wheels with about half a stroke pushing down on the pedal. Both wheels up in the air and I cannot turn them by hand. You can also see the wheel / drum pulsating on both side when you apply pressure. When bleeding, pressure is even and same fluid both sides.



Boyan

[Terry M.]

Re: 63 drum brakes pulling

John Disc Do Require A 2 Psi Check Vavle If The Master Clynder Is Below The Caipers Or Wheel Clynders 2 Psi For Disc 10 For Drum I Have Never Seen A Spring Behind A Caliper Piston? The Square Cut Seal Will Move The Piston Back Some. The Rotor Run Out Also Moves The Pads Back 2 Psi Will Not Burn Up A Set Of Brakes It Will Just Give You A Frim Pedal.

Steve,
You are right there is no spring behind the single piston disk brakes on GM vehicles -- but there are springs (at least there were originally) behind the pistons on Corvette 4-wheel disk systems. The Corvette disk/disk system has no square cut O-ring.

Do not mix up the single piston disk/drum or single/piston disk/disk systems with the Corvette disk/disk systems. There are lots of differences in these three systems.

[Kenneth S.]

Re: 63 drum brakes pulling

http://www.rochesterclutch.com/
Ken

[Wally A.]

Re: 63 drum brakes pulling

last resort, had a similar problem a few yrs. back and discovered
that one of the brake hoses leading to the wheel cylinder was bad
either blocked or swelled, cant remember....might want to check
into that.... good luck

[Stuart F.]

Re: 63 drum brakes pulling

The "Kevlar" material referred to by Ken is the same as my "Matrix Ceramic" mentioned in my previous post here. Guess it is a trade name change probably due to a trademark situation. I have found these shoes as good as my Sintered Metallics at high speed and fade resistance (Hot), yet a big improvement at slow speeds when cold. It took a while to run them in, but they are really great now at +1,000 miles or so.

Stu Fox

[John H.]

Re: 63 drum brakes pulling

John Disc Do Require A 2 Psi Check Vavle If The Master Clynder Is Below The Caipers Or Wheel Clynders 2 Psi For Disc 10 For Drum I Have Never Seen A Spring Behind A Caliper Piston? The Square Cut Seal Will Move The Piston Back Some. The Rotor Run Out Also Moves The Pads Back 2 Psi Will Not Burn Up A Set Of Brakes It Will Just Give You A Frim Pedal.

Steve -

We're talking Corvette applications here, and no Corvette I've ever seen has the master cylinder mounted lower than the calipers (although that's frequently the case on street rods, T-buckets, etc.). All '65-'82 Corvette disc brake calipers have springs behind the caliper pistons, and none of them use square-cut seals.

[Tracy C.]

Re: 63 drum brakes pulling

....... You can also see the wheel / drum pulsating on both side when you apply pressure.........
Boyan

Boyan,

If you can see or feel a "pulsating" of the wheel or drum, that is an indication of a non concentric condition. Not to be confused with an out of round condition of the drum. What I'm talking about is where the internal diameter of the drum is not centered and rotating true about the rotational axis of the spindle hub.

I would expect this to be very rare problem, but something to look for and it would be something you could eliminate by swapping the drums if the problem is limited to one side.

tc