49 chrysler rear brake adjustment

[gregchrysler]

Hello  again  how do you adjust rear brakes on 49 Chysler royal?    They work but hub is getting hot and I think they are grabbing and not letting go, restricting wheel free turning..   I don't see a hole in the back that turns the spindle to  adjust them   with the brake tool  Thank you

[auburnseeker]

The big bolts in the backing plate adjust them about half way down.  but there is a major adjustment I think at the bottom as well.  Different year mopars have different tweeks to adjusting them.  The shop manual shows you exactly what to turn and I believe which direction if it's not marked on the head of the bolt.  Chrysler brakes are a bit finickey to get right.  You also want to make sure the back rubber line isn't deteriorated inside or it may act like a check valve and not let the pressure back when you take your foot off the brake.  If it's at all an older line,  I would replace it.  They are cheap.  You will know if the line is acting like a check valve if you crack the bleeder at the wheel cylinder and it has pressure there without any pressure being applied at the pedal.  You will also want to make sure all the parts in the backing plate move freely.  Years of gunk and rust may cause them to stick.   A broken brake return spring can do it as well.  Lots of things to check. 

[Rusty_OToole]

There are 2 adjustments, major and minor. A major adjustment only needs to be done when the brakes have been relined or taken apart for some reason. For maximum efficiency you need to arc the shoes to match the drums then adjust the shoes so they make full contact. After that you need to do a minor adjustment from time to time to take up wear.

 

The brakes are very effective when put together right and adjusted right. You need a manual if you want all the gory details.

 

It sounds like yours were never put together right or adjusted right.

[auburnseeker]

After a brake job as well,  especially when everything is apart you need to give them a few somewhat hard stops to get set into place,  then readjust them as it's difficult to get everything all in the right places when you assemble it. 

[61polara]

Greg,

Have you recently done work on the rear brakes?  If so, I would start looking at the adjustments.  Either way, have you replaced the rear brake hose?  Old hoses will swell internally and block the return of fluid to the master cylinder.  Each time you apply the brakes, they will get tighter.  I would replace that hose first and then bleed the rear brakes.  Cut the old hose apart (across it) and I think you will find that there is almost no opening inside the hose.

[plymouthcranbrook]

http://p15-d24.com/page/p15d24/tech/brakes.html

 

Also check the Master cylinder relief port inside the master cylinder.

 

 

The hole is very small. Use a paper clip or an even smaller wire to clear. You will notice a small spurt of fluid inside the master cylinder with the cap off if the vent is open while gently pressing the pedal. .  If you do not see the spurt the hole is plugged. This can and will stop the brakes from releasing.

 

Edited July 13, 2018 by plymouthcranbrook (see edit history)

[jp928]

With Bendix type brakes , the backplate can be worn where the edges of the shoes slide on them, and when relined, the shoes can try to fall into the wear grooves, and start dragging - solution is to build up with weld and grind flat again. Also with a tired master cylinder, the main cup can swell with age and start blocking the small hole mentioned above.

jp 26 Rover 9

Edited July 14, 2018 by jp928 (see edit history)