Rear Drums Drag

[Stumper]

I’m at Witt’s end with these rear brakes. Car is a 62’ Fury. 10” drums without the lock nut (later make?). In the spring I replaced the shoes. Found at the time there was no self adjusting Mechanism so I installed one. First time out I drove to town and back and when I returned the freshly painted drums were smoking. They had gotten so hot the paint burned off…
I verified the adjusters were on the correct side, changed the bottom shoe springs to something lighter, scufffed up the shoes, readjusted and then my transmission issues developed so I never got to test the brakes.
The guy that did my transmission work called one day to say my brakes were dragging. He found that after the car sat for awhile the brakes would release and not drag but once it was taken out again and driven the brakes would start dragging. He found that releasing the fluid pressure at the rear would release the brakes so assumed the rubber hose was collapsing inside. It would allow fluid through to activate the brakes but not allow the fluid pressure to release when the peddle was released.
I had him replace the hose, readjust everything and according to him they were working as they should afterwards.. Today I took it out for the first drive after getting it back and after a 15 mile drive when I got home the rear wheels were real hot! As in you couldn’t hold your hand on them hot..
What am I missing? Should the rears not use a self adjusting system? Since the drums are from a later year (no locking nut) could I have gotten the wrong shoes? Would the shoes be different for 62 and later 10” drums?
I didn’t replace the cylinders since they were not leaking. Could they be sticking (both?). I’m at a loss…..

 

[Darter6]

Single or dual master cylinder ? If dual sounds like master cylinder to me.
Giveaway was when they released when the bleeder was cracked open
I had this problem after converting a single to dual on a 63 Valiant. Mine was the front brakes dragging.
New master. Pulled it apart everything looked normal, reassembled same thing.
Got another master, problem solved. My 2 cents.
OR parking brake problem ??

 

[Thrashingcows]

When you added the adjuster did you swap in the complete system with all the springs, cables, and other hardware along with the E-brake system lever etc?

 

[dadsbee]

Power brakes? Push rod is set toooo long.

 

[Stumper]

Power brakes and a newer style dual reservoir.
I added the adjuster wheel spacers, cables and springs from a set that were on the front at one time.

 

[retractable]

Brake like switch set to close to brake peddle? Brake peddle can't return all the way.

 

[dadsbee]

Power brakes and a newer style dual reservoir.
I added the adjuster wheel spacers, cables and springs from a set that were on the front at one time.

Did you take the time to set the push rod length correctly? Sounds like it's too long and holding the valve spool in, therefore the wheel cylinders can't drain back.

 

[CoronetDarter]

Did you take the time to set the push rod length correctly? Sounds like it's too long and holding the valve spool in, therefore the wheel cylinders can't drain back.

That was my problem when I first got the Coronet on the road. Felt like I was dragging a 500 lbs anchor, and the rear wheel was so hot I couldn't hold the lug nuts.
Adjusted the push rod shorter and been good ever since.

 

[Stumper]

I didn’t add the current brake master. I looked over the winter for adjustment on the rod but there was none under the dash, or so I thought. The guy that just worked on it told me he pulled the master back from the firewall and found the rod wasn’t close inside so he adjusted it at the end?? Supposedly to eliminate some slack in the peddle.

 

[Stumper]

I didn’t add the current brake master. I looked over the winter for adjustment on the rod but there was none under the dash, or so I thought. The guy that just worked on it told me he pulled the master back from the firewall and found the rod wasn’t close inside so he adjusted it at the end?? Supposedly to eliminate some slack in the peddle.

Searching tonight I am finding that there should be around 20 mil gap between the rod end and cup at rest ?
Tomorrow I’ll call the guy that worked on it and see what he set it to. Also noticed that the master reservoir was leaking pretty good when I got back with the car today. Would this also be an indication of the pressure not releasing?

 

[CoronetDarter]

That sounds about right. Too much gap and the pedal sinks to the floor.
I measured while the m/c and booster we're on the bench.
There are specific depth measuring tools, but I just used a straightedge and the tail of my calipers.

 

[Sixpactogo]

I remember Rick Eherenberg from Mopar Action Tech writing about using the older style brake cylinders with disc brakes being a problem. Something about a residual valve or something they have that won't release the fluid. Maybe replacing your rear brake cylinders with the newer ones will solve your problem.

 

[Stumper]

This morning I lifted the rear and the wheels spun freely. If the problem was physical (adjusters, shoes) I would think they would still be tight? This is telling me there is still a hydraulic issue? I took a couple pictures with the wheels off. If there is a set up problem or a shoe quality issue I don’t see it… anyone else?

 

[Ron H]

Must be a '65/later rear installed? Also appears as though a cable is missing for the self-adj? It runs to the star lever...maybe can't see it in the photo..

 

[Stumper]

The cable is there. Not sure about the entire rear end but The brake set up is definitely newer than 62’ because the drums were held on with a nut in 62’. Not sure when the change was made to these type of drums.

 

[Ron H]

'65 - I replaced the axle/housing on my '63 to a '65 Coronet. There's a guide, a curved plate that cable is supposed to run around and down to the adjuster lever; a tight fit to have no slack on that cable.

 

[Ron H]

The cable is there. Not sure about the entire rear end but The brake set up is definitely newer than 62’ because the drums were held on with a nut in 62’. Not sure when the change was made to these type of drums.

Sorry, my goof - I see the guide now. Looks a bit different than my setup.

 

[Stumper]

Not sure if I’m making any progress or not…. Yesterday I adjusted the booster rod. I measured the MC cup with a tread depth gauge at 0.9”. Then measured the rod stick out using the back end of my calipers. According to what I was seeing the rod was about .050-.060” too long. Adjusted it back to where there “should be“ (ordered the real tool last night) around .010” gap. Test drove the car. The peddle play increased a lot, but there was a lot of play before the “Ace Mechanic” played with it… Ran the same route about 12 miles and when I got back the rear wheels were still pretty hot.. Not as hot as the first time out and the right wheel seemed (also ordered an IR Temp gun last night) hotter than the left…
Needless to say I am still at wits end…. The adjuster tool should be here Monday-Wednesday and I’ll check the adjustment again then. It really sucks that I have so much peddle play when the rod is set right though. Wondering if I should get another MC with a bigger bore? I’m also thinking I need a longer (adjustable) rod from peddle to booster..
I did loosen up the brakes more after getting back yesterday so I’ll try another run when the rain stops to see if it was just shoe adjustment…

Thoughts??

 

[Ron H]

Do you have a FSM? There are good details in it to double check.

 

[Stumper]

Do you have a FSM? There are good details in it to double check.

View attachment 1487041

I do but it’s for a 62 and my rear is like yours pictured. I doubt there is much difference though.
i wish I could find out what my master cylinder and booster are from/for… I really wonder if it’s not correct for this car..