new disk brakes dragging

[sbc10guy]

i recently just upgraded my non disk brake truck to disk brake. I put new drop spindles on and a full cpp brake kit with booster. I am noticing after a short ride the pads are dragging hard to where its kind of hard to spin the tire. I tried letting the bleeders loose and it wasnt under a bunch of pressure. The tires still wouldnt roll good. I unhooked the rod from the booster to the pedal assembly completely and they still will not let go. I can spin the hub either way and watch the pads move with the small amount they have to move so i can tell they are pushing on the rotor. Any ideas on where to look now. Im out of ideas. Thanks

[RodnRudy]

It's normal to have a slight drag on the front rotors on a disc brake system.
I have the CPP front disc set up on my 68 and it has the drag you are experiencing.

[sbc10guy]

Does yours get pretty warm? I know mine is pretty hot after a few miles but maybe that is because its relatively new. It just doesnt seem right to me i guess. I can feel it dragging when i let off the gas at low speeds.

[RodnRudy]

Sure they get pretty warm but that's just friction. if you had a line pressure problem the front brakes would be smoking hot, you'd probably smell the pads.

[sbc10guy]

ok well that makes me feel a little better anyway. Im assuming it will slowly go away as well then?

[A1971Blazer]

Be sure the calipers are floating and not in a bind and not sticking .... there shouldn't be enough drag to keep you from turning the wheel by hand

[sbc10guy]

Ok i feel like they are not, but i will for sure check that out before I put it back together.

[TheFix]

You may need to adjust your rod on the brake pedal. I had to adjust the play on mine after installing the same kit. After I installed it, at rest, the pedal was pushing the piston in half travel already.

[sbc10guy]

well i noticed that if i have the caliper loosely bolted in place the rotor spins freely. As i tighten the 2 bolts on the caliper the rotor becomes harder and harder to spin. Is this a problem that i can easily fix or is that something normal.

[A1971Blazer]

It sounds like the caliper is binding somewhere....pull it back off and remove the the pads....put the caliper back on and bolt it down.
Then make sure it will move back and forth freely on the pins......it has to float....a little grease on the slide pins (not the bolts) will help.

[snipescastle2]

just asking, are the brake hoses/lines/master cylinder all for disc brakes? if the master cylinder isn't meant for disc brakes, it may have residual check valves keeping pressure inside the calipers causing your pads to drag....the square seal inside the caliper is designed to flex a little to allow the pistons to retract, albeit a very minute amount, but if there is residual pressure holding the pistons out....well go figure.... food for thought.
Have a good one!
Ben

[sbc10guy]

I can see a small bit of the piston sticking out of the caliper, maybe 1/8 inch. I cannot get that squeezed back in all the way even with the bleeder let loose. I also put the caliper on without pads and measured to the rotor and it seems to be perfectly inline. There is no sliding the caliper on the pins even a little though. I greased it but it seems like it is not supposed to move on them. Stlll at the point of it locking up when i tighten the caliper on. It was all bought in a kit for disk brakes from cpp so it should all match. i even adjusted the rod to the pedal and took it completely off and it still binds up. im about out of ideas and would love to be driving my truck.

[A1971Blazer]

Originally Posted by sbc10guy

I can see a small bit of the piston sticking out of the caliper, maybe 1/8 inch. I cannot get that squeezed back in all the way even with the bleeder let loose. I also put the caliper on without pads and measured to the rotor and it seems to be perfectly inline. There is no sliding the caliper on the pins even a little though. I greased it but it seems like it is not supposed to move on them. Stlll at the point of it locking up when i tighten the caliper on. It was all bought in a kit for disk brakes from cpp so it should all match. i even adjusted the rod to the pedal and took it completely off and it still binds up. im about out of ideas and would love to be driving my truck.

In my opinion without actually seeing it......there has to be some kind of issue with the caliper, pins or bracket.....

The caliper absolutely must float on the pins to function properly. The floating allows it to center itself on the disc as you apply the brakes and equalize the force on both pads otherwise just one side (piston side) would be making contact.....or binding against the disc as it appears to be doing.
is it possible to post some pictures...? post a link to the kit you're using

[firedemon]

is it like a wildwood setup some of those bolt on and have to be shimed if its a factory type setup it has to slide on those pins got pics

[sbc10guy]

pics should be up in a few min

[sbc10guy]

Here is the pins. everything seems to be completely solid and both pads are very tight to the rotor.

[sbc10guy]

There is a bushing that is in the caliper by the threads or the head of the pins and it is tight to the bolt head and the caliper mounting bracket. That seems to hold it solid is that correct?

[firedemon]

yes that is supposed to be there but it looks mushroomed a little it should slide on that bushing and the head of the pins . with everything being new id expect it to be more on the head of the pin being that close to the spindle gives you almost no wear space like its pulled in too much

[firedemon]

looks almost like the rotor is a little far away from the spindle pulling everything out with it putting force on the pads

[A1971Blazer]

Kinda hard to tell but is there a small sleeve that the pin bolt goes thru on the back side.. if that's it....it does look a little mushroomed.
The bolt should tighten on the sleeve to hold the caliper in place and the caliper then floats back and forth on the sleeve....also you should be able to push the piston in enough to open up some clearance between the pad and the disc when you first put it on....after that it should center up and the pads will just touch slightly on the disc.....I'm afraid if you drive it a lot you could heat the disc up enough to possibly warp it.

[firedemon]

its a little hard to tell from this pic but best I could find but see how the pins stick out a little on this side of the caliper that is the way most all I have done look makes me think your rotor is a little out holding the caliper out not letting it center properly . then the caliper will be more to the inside so it has more room to slide when it wears . I read another post where someone had problems with the chineese bearings that came with their cpp kit . not saying this is it but it seems to be a little off by the pics something is holding it out just a little too far . those bushings are usually the same size as the pins too and yours look a touch bigger like they were mushroomed on the head side like maybe over tightened a little that could keep it from sliding on the pins

[sbc10guy]

The bushing is not mushroomed at all that is just excess grease you see in the pic. It is almost as if the bolt head sandwiches the caliper to the bracket not allowing any movement because the bushing hangs out both sides too much. I know on my car there is plenty of movement. This thing zero. And yes im not driving it again. It gets very hot. The pads barely slide over the rotor when i first slip the caliper over. Even completely unbolted, no pins in it, it has slight friction.

[sbc10guy]

It almost does seem as if the rotor could be too far out but it is tightened on nicely and spins good so i cant imagine its not on all the way.

[firedemon]

ok I see the greese

[firedemon]

but if you believe the rotor is all the way where its supposed to be I'm thinking it could be bad caliper