Wow. I have been reading some of the threads and now my problem seems small.
I will set this up with a little history first.
Brakes dragging only on the right front, Most of the time.
This is a 1976 Dodge B200 Van, 318cu, auto, power brakes.
This also sat for almost three years out in the elements. (I know, I should be horse whipped)
Been replacing belts, hoses etc and had done the brakes not too long before I parked her.
Started driving her again, pulling and moving some of my boats from up in Washington down into Oregon.
First trip down to Oregon, I noticed, Wow, I just did a tune up and might need to pull the carb off and go though it as the mileage is bad now too.
The van was loaded heavy and the boat on the back was also loaded pretty heavy. Pulled into a rest stop and didn't seem to notice any issues stopping, other than I had to dive on the brakes pretty hard.
Going back out on the freeway, I noticed her shaking like I had a tire coming apart, belts broken and getting ready to blow out.
Felt the tires, no, all round and hard, no bulges?? Felt the hub and the right front was Hot, too hot to hold on too.
Left side was fine.
Now that I am on the freeway, I need to get off at the next exit I think so I head out again and same vibration and all of a sudden, it starts to go away.
Then I notice, its gone, no vibration at all.
This time I kind of roll off the side of the freeway and use next to no brake peddle to stop, felt the hub and it was even Cooler than before.
After about two or three hours on the road, I forget about the problem as it went away.
(I don't believe in self healing either)
Then a few days later, no load in the van, going over to a friends house, it starts that whole thing over but only this time, I don't remember having to Dive onto the brakes to make it happen.
I was able to get it off the road, put the jack under it and the left wheel, I could turn with the standard amount of resistance for disc brakes. The right side, I was not able to turn the wheel.
I parked it, ordered a new master cylinder for it, did the bench bleeding, check the dept of the plunger as I know they can be different, but it was the same. What I did not do was check the hole size.
Bolted on the new master, jacked up the front wheels and gave them a spin and both felt fine.
After a few days of driving, it all started happening over again.
Here is what I have done up to this point.
I pulled the master loose and checked the hole size and made sure I had the same clearance as I did with the old one (it worked fine for 5 or more years before parking it)
Made sure the plunger was all the way back, still had the right front brake hanging.
Check the vacuum booster for throw as well as fluid that may have leaked in over time, all clear, nothing hanging up or catching.
Pulled the right front wheel and used a large screw driver in the fins to spin it. Its still hung up.
Pulled the two bolts that hold the anti rattle and hold down braces in place.
As soon as those anti rattle plates were moved, I did see that I was able to mussel the caliper and make it move by hand so it was not hung.
So, the question that I am wondering about. Does a 1976 Dodge B200 (1/2 ton) Van have a Limiting valve? on it?
I did see a block on the left side, top of the frame were it looks like only the brake lines go in and out of. No wiring or centering valve that I could see.
Now, because I was Stuck with it out of town were it happened to me, the only thing I had to purchase was a cheap 6 inch "C" clamp to compress the piston on the caliper.
I was able to just pull the wheel, compress it about 1/4", pump the brake peddle back out, compress, pump it back out, compress, pump it back out.
The brakes are working like they should, again, for how long, no clue...
So, here I am, stuck away from my shop and not sure what parts I should go for.