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Discussion Starter #1
Well I finally have my 57 back on the road after a year of upgrading. Engine & Tranny swap to 355/TH350, power steering, power disc front brakes, dual master cylinder, new front suspension, 2.5" stainless dual exhaust, headers, body off frame under carriage and frame cleanup, new body mounts, u-joints, etc. Now I have a couple of problems I need your help and wisdom to resolve.

I drove the car about 10 miles yesterday and started smelling something burning. I noticed my brakes appeared to be engaged. All four wheels were very hot to the touch all the way up to the tire. This morning the brakes appeared to free up and I could move the car by hand while in neutral.

Tonight I loosened my emergency brake cable thinking maybe the exhaust install had made the cable tight. Also my exhaust is about 1.5 inches from my rear brake line. Could brake fluid heating up cause the rear brakes to stay engaged?

Tonight I drove the car about 3 miles and noticed the front disc brakes were starting to stay engaged. The brake pedal became stiffer the more I drove. I am a rookie so any wisdom on what might cause the front disc brake problem would be appreciated. Disc brake kit is from Speedwaymotors and includes 11" brake rotor, 1969-72 Brake pads, GM rebuilt 1969-77 calipers. Dual reservoir master cylinder, disc/drum proportioning valve and 8" dual diaphragm booster came from CPP. New front 3/16" brake lines. I also upgraded the front wheel bearings but I was careful to pack them properly. I have concern the heating is cooking the wheel grease.

Any ideas are much appreciated. Thanks, Todd...
 

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Trifive Automotive Electrical Wiring Expert
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The rod from the brake pedal to the booster is too long. You need a little freeplay in the pedal before it moves the booster. When it's adjusted correctly, you will be able to feel the pedal contact the booster when you push the pedal an eighth to 1/4" with your hand. The rod is holding the master cylinder piston in at rest and not allowing the fluid to return to the reservoir. As it warms up, the fluid expands and causes the brakes to drag.
 

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Todd, 3 things come to mind.

First, do you have a master cylinder from a 67-69 drum brake car? That m/c may have residual valves in the outlet ports and you don't want them if you have discs.

Second, is the brake pushrod between the pedal and the booster preloaded? You don't want that. You want a tiny bit of free play.

Third, is there preload between the booster and master cylinder? Same deal, you want a tiny bit of free play.

We are in the same city, never met, I would be glad to come over and help you look at the problem. It's time we met anyway if you solve it before I get there.
 

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Discussion Starter #4
Thanks Don and Rick. I had ensured I had the proper play between pedal and booster when initially installed. I will double check.

Rick, I would love to meet you. I live off Mason 3 miles south of I10. Anytime this weekend or pretty much any weekend is good. Let me know and I will buy you a coke, beer or what ever you drink. I will pm you my phone number.
The booster, master cylinder, proportioning valve and brake lines are from Eckler's 20-03 brake kit which is really a CPP product. So I am not sure the master cylinder year. I will ensure the brake pedal has plenty of play to eliminate this as the problem.

Thanks again guys for your help...
 

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Todd and Rick,

I am one stoplight south of I-10 at Dairy Ashford.

I am new '55 owner. I am trying to get my hands around what is stock/correct with my car. I would love a keen eye.

I am around mostly on Saturday, although thinking of driving to Popular Concepts to look at what they have.

Make it an "around the world party" and a three-stop tri-five day...

Mike
713-203-2483
 
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