All 4 brakes dragging BAD

[Casperfast]

Took the mustang to yhe parts store to get a new cts. While on the way there is felt like the brakes were dragging, by the time I got hom about 2 miles I had to give half throttle to go 25 mph. When I got home all 4 were smoking. All brake parts minus calipers in front have 8 miles on them. New master, booster, pads, shoes, rear cylinders. All bled until clean. Wth is going on. Did my master take a crap? 72 w/ disc drum power

 

[Don C]

The first thing I would check is the push rod clearance.

 

[Casperfast]

I thought of that, but when I drove the car yesterday it had no brake issues. Ive driven it a few times down the street and back since I did the brake work

 

[will e]

On my jeep I had the same problem. What happened is the 'c' clip retainer at the back of the MS broke into a few pieces. A couple of them fell in front of the 'c' clip and that kept the pressure on the brakes. It's a bit of a long shot but easy to check.

 

[Casperfast]

Thank you, I will slide the matter off and look

 

[Bill73Ragtop]

The first thing I would check is the push rod clearance.

Agree! Check for proper air gap.

 

[computercarguy]

If it is a power brake system that was working properly, I would suspect the valving in the vacuum brake booster allowing vacuum assist when you don't want it. Unplug the vacuum booster and see if the drag stops. Remember you will not have your power assist so eat your Wheaties! If the drag stops then you have to figure out if pressure is being applied to the brake booster or if it is the booster itself causing the problem.

 

[c9zx]

I thought of that, but when I drove the car yesterday it had no brake issues. Ive driven it a few times down the street and back since I did the brake work

It may not shoe up for am mile or two and get progressively worse as the brakes heat up. Been there done that.

Chuck

 

[Casperfast]

i ended up cracking the brake lines loose at the master and they released. so i replaced the new master with.... another new master. havent driven yet but i will see in a week or two after i get the engine back togather.

 

[mjlan]

If there was pressure on the lines make sure that the rod from the pedal isn't pushing on the M/C piston.

Also, 'new' can mean different things. Is it really

A brand new master or remanufactured?

 

[Mikes73]

As mentioned check the master cylinder push rod. I had the same exact problem and the push rod was the culprit.

 

[Stanglover]

Maybe this little trick will help set the push rod clearance. Get a small pieces of plastisine, roll into a pill and drop it in the M/C piston cup (where the push rod goes in). Replace the M/C, no need to tighten the nuts, but hold it firmly in place. Then take it off and see how much the push rod squished the plastisine. If it went right through, you have no clearance. Loosen the lock nut and turn the push nut to back it off and try again until you get about .015" clearance. Now do it again, but this time tighten the nuts to make sure you have clearance. i.e. you have a thin piece of plastisine at the end of the rod .015" thick. Hope that is understandable. Let us know what you come up with.

 

[Don C]

Another trick is to pull up on the brake pedal with your foot, the bump stop should be soft enough to pull it up enough to release the brakes if it is a push rod length problem.