65 Brakes

[Buck]

65 T Bird brakes. My brakes are extremely touch. At slow speeds it is difficult to apply them lightly enough. At higher speeds they can easily be applied too hard. Could the vacuum booster be from a wrong year? I replaced the master cylinder already. Is there possibly a vacuum valve that limits the amount of vacuum?

 

[DEVIL DOG 62]

65 T Bird brakes. My brakes are extremely touch. At slow speeds it is difficult to apply them lightly enough. At higher speeds they can easily be applied too hard. Could the vacuum booster be from a wrong year? I replaced the master cylinder already. Is there possibly a vacuum valve that limits the amount of vacuum?

Make sure the rotors or drums aren't out of round. If they are it would make it grab faster because they're out of round. Wouldn't hurt to replace them along with the drums or rotors. GOOD LUCK

 

[64ZCODE]

Agreed. Additionally, the arc of the brake shoes may not match the arc of the brake drums once the drums have been turned, meaning the brake shoes may not uniform contact the drums. This should be evident by examining the shoes. Leaking brake fluid, even a little on the drum, can cause grabby brakes too. Also, others with similar issue have commented the replacing rubber brake lines with metal clad ones can improve braking for drum brakes.

 

[Gary Tayman]

The 1965 was the first year for front disk brakes, so there are no drum problems unless it's in the back. However if those flex hoses are old, replace them. They tend to swell inside, and brake fluid does not easily flow back when the brakes are released. In fact, it's a very wise idea to replace ALL the brake lines, especially the line that goes to the back. There is a spot, right where the line (and fuel line) turns to go toward the back, under the door hinges, where there is a small plate that protects these lines. Instead of protecting them, mud gets caked in there and rusts the lines. One day the brakes let go and you go for a joy ride. Buy new stainless steel lines and you're good.

Also, the disk brake cars have a proportioning valve that can wreak havoc. Check that. Bottom line, if you have a 53-year-old car that's never had a major brake overhaul, you should really get a major brake overhaul.

 

[Buck]

Thanks for all the above suggestions. The rotors were replaced a few thousand miles ago and did not improve the situation. The booster and master cylinder have also been replaced along with the flexible lines. Confusing the problem is that I had a creeping brake pedal for awhile even though the master cylinder had been replaced. I replaced that master cylinder and the creeping pedal went away. I did not know about the proportioning valve and will have to look at that. Can you tell me where is the proportioning valve located?

 

[64ZCODE]

Hi Buck. I'm looking at having to replace my booster and master cylinder as well. Wondering where you obtained yours? Also, did you go with a dual diaphragm master cylinder? Thanks!

 

[DEVIL DOG 62]

Thanks for all the above suggestions. The rotors were replaced a few thousand miles ago and did not improve the situation. The booster and master cylinder have also been replaced along with the flexible lines. Confusing the problem is that I had a creeping brake pedal for awhile even though the master cylinder had been replaced. I replaced that master cylinder and the creeping pedal went away. I did not know about the proportioning valve and will have to look at that. Can you tell me where is the proportioning valve located?

Usually follow the lines down coming from the master cylinder. They all should attach to a square valve with 4 lines going to and from it. That's your proportioning valve. GOOD LUCK