Thread: Front brakes locking.

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Can you take more pics of the back pad.

Did you lube all the contact points for the back pad. Are they free of paint and rust.

Maybe you have the front & back brake lines crossed backwards & the proportioning valve is holding the front calipers out.
Had this happen to me on a disc brake swap & that was the problem......joe

Thanks guys I will check those things later. sfort no I didn't lube the back of the brake pads. What does a guy use to lube them ?

I've had several Fords that have had problems such as you have described and the "cure" was to disassemble, clean the slides, chip off any rust, lube with high temp grease then reassemble. My '79 Mustang needed to have that done every 12-15 months. The most costly one was my current '06 F350 which cost a pair of calipers, rotors and pads. Now I 'fix' it yearly as well.

And that proportioning valve is probably not needed.

Also, check the MC for a resid check valve too

Originally Posted by IC2

I've had several Fords that have had problems such as you have described and the "cure" was to disassemble, clean the slides, chip off any rust, lube with high temp grease then reassemble. My '79 Mustang needed to have that done every 12-15 months. The most costly one was my current '06 F350 which cost a pair of calipers, rotors and pads. Now I 'fix' it yearly as well.

And that proportioning valve is probably not needed.

Also, check the MC for a resid check valve too

How do I check the MC for a residual valve? Could any of that stuff cause my brakes to not have a firm feel to them?

Originally Posted by Louey

Check these area's for the outer pad not tight enough on mounting, and the o-ring on the bolts.
If you take the caliper off, and the outer pad just falls off, you do not have it fitted correctly. Way to loose. Must fit tight. Bend tabs until you have to use a channel lock plier to seat them on the caliper. The inside pad, make sure you have the spring clip in place, and installed correctly into the caliper piston. While your at it, make sure that dust boot is not torn.

Wow thanks for going to all the trouble to illustrate what you are talking about. My outer pad does fall right out so I will fix that as well. What dust boot are you talking about?

Originally Posted by Louey

Once you take the caliper off, and remove the pad covering the caliper piston, you will see a rubber boot type seal. If that is torn, it must be replaced, or you will get dirt, water in there, and cause all kinds of problems.

that is kind of what I thought you were talking about. The calipers are new and the boots are in good shape. Thanks

Originally Posted by TooMany2count

Maybe you have the front & back brake lines crossed backwards & the proportioning valve is holding the front calipers out.
Had this happen to me on a disc brake swap & that was the problem......joe

You know I am going to have to check again but I may have this wrong as well. On a typical master cylinder is the cylinder closest to the booster for the front or rear brakes?

Originally Posted by Mr Smith

On a typical master cylinder is the cylinder closest to the booster for the front or rear brakes?

front(look at the pic I posted above) && it should also have the larger reservoir IF your running disc brakes...joe

Originally Posted by TooMany2count

front(look at the pic I posted above) && it should also have the larger reservoir IF your running disc brakes...joe

That is pretty much the way I have it with one exception. I blocked off one front port and ran the front to a T and then to the front brakes. I didn't have any directions for my proportioning valve. I did read wildwoods directions for their adjustable valve and they said it is fine to block off one port and run it to a T. Any idea if it is okay to run the non adjustable one the same way?

Originally Posted by Mr Smith

How do I check the MC for a residual valve? Could any of that stuff cause my brakes to not have a firm feel to them?

Some of the Ford and early Corvette MC had residual/check valves at the outlet.

While I don't know what you have for a proportioning valve, I think that I would try and remove what you have and install an adjustable version. At less then $40 and some tubing might just make a difference. I have Wilwoods on all four corners of my '31 along with one of their adjustable units - and it's wide open at present. And the brakes - the rears on mine are 12" with the fronts 11", so for all intents I have more brake power on the rear then the front, and they stop just great - straight line and quick - after about 6 different break in cycles which was a thread of mine last year.

That three hole valve is called a 'hold off' valve by ECI - which I found on an earlier car to be a POS. Is this the one?



As far as which MC reservoir - the largest always goes to the front. This means if you mount the MC under the floor, it will usually be 'backwards' and you need to make plumbing to adjust for that

My master has equal reservoirs but the outlet is larger in the front.(closest to the pump I guess you would call it.) In the first pic the left is the front of the car. It was hard enough to plum it in while the body was off as you can see I don't have much room under there. Nobody that I can find has any valves around here. If I change it I think I will go with a valve to adjust the back only.

I was taking a closer look at the way these calipers are mounted and I don't understand how they could possible float back and forth. The pins that mount them has a sleeve on the end then screws into the mounting bracket holding it securely against it. Am I missing something here? How could the caliper possible float to activate the outside pad? I am attaching a pic from speedway that shows how they are mounted. I didn't get mine from speedway but they mount the same way.

The calipers don't float the rear brake pad slides on various parts of the caliper. Thus the need for those contact points to be clean of rust and paint. On the pic above you can see that the pad close to both sides of the caliper as well as the two long mounting bolts. Both need to be clean and lubed. The sides of the caliper could be the problem with binding. Check and see if there is a spot that looks like it is digging in.