HELP! 11.75 brake upgrade....dragging!

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superdart

superdart

Shade Tree Tinker Gnome.....
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OK, I just installed 11.75 brakes (all new) on my '75 Dart.

I used all new stuff (Bendix Ceramic pads, Rich's Slotted Rotors, Timken bearings, rebuilt calipers and Lucas grease) and everything was installed per the FSM.

But, after bleeding, the front wheels seem to be dragging. My old 10.7" slider calipers seemed to be doing this also...any ideas?

I used the anti-rattle spring on the outside, but not the positioning clips on the backside (not available AFAIK).

Any ideas? I have done plenty of brake jobs and never ran in to an issue like this.

Second image is a video..I have NOT driven the car yet.

DSC_0006.jpg


 
sounds like the caliper isnt returning completely,,,i cant imagine the rotors are to thick,,,,,did u get paint some place that its not allowing the caliper to slide completely?
 
Actually it's powder coating, but I masked off all of the critical clearance areas so there would be no interference. The caliper didn't seem tight when I mounted it. I guess it could be dragging on the rubber bushings that the pins center on?
 
i recently replaced both calipers single puck on my barracuda they are from a 73 and up dart,,with rebuilts from the local auto store,,,neither one would return completely , making it so the rotor wouldnt turn freely,,if i grabbed the caliper and pulled it towards me it would free up,,,i took them back,,,painted,,,and got another set,,,painted them,,and they both worked fine,,,im guessing they didnt clean out the cavity real well when rebuilding them, on the first pair,,,but to have both do it was a fluke im guessing,,im glad it wasnt one and one,,,
 
I see you switched it over to pin-style calipers!

It's possible that its not sliding on the pins like it should be, although that's usually a bigger problem with the slider type calipers, they can bind up if they get dirty/rusty.

If you had the problem with your old calipers, and are now having it again with your new calipers, I would tend to suspect something else. I assume that you probably had to change the fluid and bled the brakes when you installed the new calipers? Check to make sure none of your brake lines up front are pinched, keeping fluid from moving freely in the line. If that all checks out, I would move on to the master cylinder. If both front calipers are dragging, and were before the brake swap, a problem with the master cylinder or the brake block would be my guess.
 
Oh,just thought...Have you changed your flexlines?Old ones will swell inside causing restricted brakefluid flow.Just a thought.:D
 
are you sure they didn't sell you a drum brake master cylinder?
the residual pressure valve in a drum brake M/C will cause disk brakes to drag

X2 on pettybludart bad flex line, just had that happen on my truck
 
Well, I haven't replaced my master cylinder yet. I was under the impression that the residual valve was only on the rear reservoir, and was no longer in use by the time my '75 was built.

The rear discs BTW (Jeep kit) are not dragging at all.

My lines are brand new braided lines.

I am going to take the calipers off tomorrow and make sure nothing is binding.
 
When you put in your rear disks, is that when it started dragging on the old calipers? Did you change the Master cylinder, or go from power to manual brakes?

When I switch from power to manual, I had the brake rod mis-adjusted, with the same dragging, even caused the pads to discolor.
 
No, it was dragging before the rear disc change. The master cylinder is the same one that was in the car when I bought it 11 years ago, and I've been driving it. The car drives great, but when you get it in the air the tires just don't spin like I think they should. Then again, the old brakes were slider type, so that have been part of that issue.

The car was originally a power brake car, but was converted to manual at some point before I possessed it.
 
Maybe a couple more clarifications, to go along with fstfish66:

1. Did it start dragging on the old calipers suddenly, gradually, or ????
2. Had you changed anything on the old setup that coincided with it starting to drag, eg new pads, etc?
3. How high is the pedal, and how far does it have to be depressed before it starts braking the car?
 
See if the pad is hitting a step edge at the inner diameter of the brake face on rotor. There looks to be a shiny line where the center changes to the rotor face.
 
have you tried opening up the brake line or bleeder to see if the dragging may be caused by fluid pressure or mechanical....eg if you open the line or bleeder and it goes away trace the issue to MC, pedal rod...ect etc, if it doesnt go away its at the wheel, pads to thick, sticky slide, etc etc...
 
Hey Superdart, not to distract from your original question but i'll be doing this upgrade soon and what are rich's slotted rotors? Thanks!
 
check your brake light switch. you could have tweaked it some or it just needs to be adjusted. it could be keeping the pedal pressed down slightly.
 
Problem solved...The new pins seemed to be binding a bit, and when I checked them they seemed kind of rough. I chucked them up in my drill press and ran some fine grit sandpaper over them to smooth them out. Now they spin much nicer.
 
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