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dclewallen
05-08-2005, 06:41 PM
I've got a 53 Stude. Commander that has the Turner disc brake conversion. I've put an 8.8 Ford rearend in it with all new brake parts {shoes,hardware,wheel cylinders etc}. I have a dual master cylinder {new} with residual pressure valves front and rear. Its been working and stopping fine. The other day the rear brakes did not retract and really heated things up. No damage so far but what should I look at first to determine the cause? Help. I'm fixing to take the car to the paint shop and need to repair this first. Thanks, Dclewallen

Darryl C. Lewallen

Sonny
05-09-2005, 11:17 AM
quote:Originally posted by dclewallen

I've got a 53 Stude. Commander that has the Turner disc brake conversion. I've put an 8.8 Ford rearend in it with all new brake parts {shoes,hardware,wheel cylinders etc}. I have a dual master cylinder {new} with residual pressure valves front and rear. Its been working and stopping fine. The other day the rear brakes did not retract and really heated things up. No damage so far but what should I look at first to determine the cause? Help. I'm fixing to take the car to the paint shop and need to repair this first. Thanks, Dclewallen

Darryl C. Lewallen


First thing I'd do is give Jim Turner a call, but it sounds like you need an adjustable proportioning valve. Residual pressure valves work fine for drum brakes but not so for discs. Give Jim a call, I know he'll have the right answer for ya.

Sonny
http://RacingStudebakers.com

Mike Van Veghten
05-09-2005, 02:56 PM
Residual pressure valves don't work on disc conversions.........
Hmmmm, I must be doing something wrong!

My Lark with disc in the front, stock rear drums, with res. valves (2lb., 10lb.) frt. and rr, 10 years, and stops fine.

My Conestoga with discs at both ends with res. valves (2lb., 2lb.) for both ends, works great. Though it's only got about 150 miles on it so far, I see no reason to expect problems.

Neither have disc drag that can't be overcome by turning the frt. disc with two fingers on the lug studs.

Sonny
05-10-2005, 01:17 AM
quote:Originally posted by Mike Van Veghten

Residual pressure valves don't work on disc conversions.........
Hmmmm, I must be doing something wrong!

My Lark with disc in the front, stock rear drums, with res. valves (2lb., 10lb.) frt. and rr, 10 years, and stops fine.

My Conestoga with discs at both ends with res. valves (2lb., 2lb.) for both ends, works great. Though it's only got about 150 miles on it so far, I see no reason to expect problems.

Neither have disc drag that can't be overcome by turning the frt. disc with two fingers on the lug studs.



I might stand corrected on that Mike. I'm sure that some setups can't use residual type valves, that's why I suggested talking to Jim, he'll know for sure and hopefully post an answer for us too.

Sonny
http://RacingStudebakers.com

Mike Van Veghten
05-10-2005, 10:14 AM
Sonny...

P.S., I picked out a hand full pictures of my Lark to send you...just haven't shrunk them all to e-mail size yet.

Worken on it...

Mike

N8N
05-10-2005, 10:39 AM
In a setup where the master cylinder is lower than the front wheels (such as a C-K or pre-'61 car with a frame mount MC) the 2 lb. RPV may provide for a little firmer pedal by keeping the fluid from draining back into the MC and allowing the pistons to retract and/or pulling air around the caliper seals. With a firewall mount MC the RPV is not needed with discs.

A 10 lb. RPV should not be too much for the rear drums; are the return springs in good shape? How about the rear brake hose?

nate

--
55 Commander Starlight
62 Daytona hardtop
http://home.comcast.net/~njnagel

Sonny
05-10-2005, 10:55 AM
quote:Originally posted by Mike Van Veghten

Sonny...

P.S., I picked out a hand full pictures of my Lark to send you...just haven't shrunk them all to e-mail size yet.

Worken on it...

Mike


You're "Da Man", thanks a million Mike!

Sonny
http://RacingStudebakers.com

Mike Van Veghten
05-10-2005, 03:31 PM
N8N,

Just another thought about residule valves.

My master cylinder is under the floor (Conestoga)...but it's a remote, with the reservour in the engine compartment. So in my case, there is no drain-back.
After talking with a few roundy-round racers, I went with what they do, valves "and" high mount reservour. Very good feel and action.

Just another mouse trap design.

Mike