Disk Caliper wont go back on

[72Ruster]

72 Duster with front discs:

Pulled the car into my garage to do the wheel bearings today. First side was a pain in the ***, broke the transfer tube somehow and had to fab one up, the wheel on that side seems to be dragging the brakes. Barely turns, finger tight on the retainer nut and cotter pin in. Spins fine without the caliper. I did not disconnect the flexible hose. (Should I have?)

The the next one went pretty smooth until i had a problem with the cotter pin and lock nut. It seems like the cotter pin had to go in at an angle like the nut wasnt going far enough. Checked the races of the bearings but they seem in there.

MY MAIN ISSUE: The caliper wont line up with the mounting points on the back. I tried compressing the pads. but it just seems off, like its not even very close. Messed with it for about an hour and now my back is killing me. Please help me. Im new to Mopar and haven't worked on old cars in many years.

 

[AJ/FormS]

A picture would help.

 

[AJ/FormS]

It seems like the cotter pin had to go in at an angle like the nut wasnt going far enough. Checked the races of the bearings but they seem in there.

IMO
take it apart,check to be sure the seals are correct and seated deep enough. If they are, then;clean out the grease , knock out the races and verify that what you put in, is the same as what you took out, and that the cones properly fit in the cups. While they are out you can verify that there is not something at the bottom of the bores that is preventing the bearing races from seating, especially the inner one;on account of that could cause both of your problems. In my experience with those brakes, there has always been ALMOST TOO MUCH room for the cotterpin.
If you didn't change the pads, then you should not have had to push the pistons back in, other than to clear the ridge at the outer diameters of the rotor. That should have been a clue.
Pushing all 4 pistons back in evenly can be a chore.
If the master cylinder was full before you started, that returning fluid has not got much place to go, except up into the cap.

"seem in there", is not good enough. If they move later, while your motoring down the hiway ........ God only knows what could happen, and it won't be anything good.

 

[72Ruster]

A picture would help.

Took the caliper off, Put the car on the ground and called it a night. The cotter Pin was maybe a 1MM difference from when I took it off. Used the same parts on the other wheel. The caliper mounting bolts I'm talking about:

 

[moparmat2000]

I usually tighten the spindle nut snug while turning the rotor to seat the wheel bearings. Once seated, I back off the nut then make it hand tight. Otherwise the bearings will be too loose in the races, will destroy themselves. you will eventually feel it with a clunking and loose feeling in the front end.

As far as the calipers go, of course the left one will feel tight if you pushed the pistons back on the right one to put it back on. You moved the fluid back to the left wheel by compressing the pistons on the right side making them compress the left brake.

The proper way to compress front brake caliper pistons is to take the lid off the master cylinder. Hydraulic fluid will push upward to path of least resistance. This is why when your brake fluid is low, check your pad wear first. As the pads wear and pistons move out to maintain rotor contact, the reservoir fluid gets low. I dont add fluid when it gets low. Because when you push the pads back, the reservoir will then overflow.

Maybe your pads on the passenger side arent pushed back far enough giving you enough room to move the caliper around.

 

[Demonic]

I have put a bleeder hose on and opened a bleeder while moving the caliper with a pry bay to push the pistons back. Regular fluid changes are important if you are running the 4 piston calipers.

 

[moparmat2000]

I usually get a friend to pour in new fluid, and I use a vacuum bleeder on all 4 wheels until the fluid comes out clean. Done this on my pickup ever couple years since it was new. Never had any issues with rust in the lines and it's now 25 years old.

 

[72Ruster]

IMO
take it apart,check to be sure the seals are correct and seated deep enough. If they are, then;clean out the grease , knock out the races and verify that what you put in, is the same as what you took out, and that the cones properly fit in the cups. While they are out you can verify that there is not something at the bottom of the bores that is preventing the bearing races from seating, especially the inner one;on account of that could cause both of your problems. In my experience with those brakes, there has always been ALMOST TOO MUCH room for the cotterpin.
If you didn't change the pads, then you should not have had to push the pistons back in, other than to clear the ridge at the outer diameters of the rotor. That should have been a clue.
Pushing all 4 pistons back in evenly can be a chore.
If the master cylinder was full before you started, that returning fluid has not got much place to go, except up into the cap.

"seem in there", is not good enough. If they move later, while your motoring down the hiway ........ God only knows what could happen, and it won't be anything good.

Thanks for this. I usually just assume I did things right the first time. Took it back off, cleaned everything out really well, re-seated everything and got the clearance I needed. Left the caliper off all night and and was able to slip it on no problem. Bled the brakes with the wife and took it out for a spin. All issues fixed!