56 Brake Drum and Backing Plate Getting Hot

[junkyard junky]

The passenger side rear brake drum and backing late are getting hot on my 56 coupe deville. Previous owner Installed new shoes and wheels cylinders along with turning the drums. Last year I had the same issue and pulled the wheel to check everything out. Didn't find anything strange but I did back the adjuster off a little. Well the car sat from then until recently. Took the car down the road and back (about 2-3 miles). Got under the car with a handheld thermometer and the drum at the bottom was 228 degrees, backing plate was 178 degrees, and the end of the axle housing where the flange is to bolt the backing plate to was at room temp (about 78 degrees). This was all on the right side. Went to the driver's side rear and the drum was about 60 degrees cooler. So I'm thinking I still need to back the adjuster off more first. Last year when I first had this problem I checked the axle shaft for excessive movement and did not detect any. Anything else besides maybe the brake shoes being a little too tight?


J. Rutledge

[Alan Harris CLC#1513]

Stuck wheel cylinder? Weak return springs? Crud in the brake line?

[Jon S]

Collapsed rubber brake hose releasing slowly. Does wheel spin free jacked up?

[Roger Zimmermann]

I had that problem with one drum on my '56 de Ville. The return springs were too weak; the problem went away with new springs.

[TJ Hopland]

I too was thinking return springs.   Also check to make sure the backing plates are nice and smooth, sometimes you can get a groove worn in em and the shoe will get caught in the groove and not be able to return.

[Scott Halver]

I had a similar problem on the driver's side 1960, rear brake.......... long story,.....   turned out to be a "hot spot" on the drum.   I adjusted the brakes to what I considered "correct" then drove the car very easy.  After a couple of miles and one or two backups as part of just turning the car around (not backing to intentionally adjust-up the brakes via auto adjusters), I then noticed a grabbing and that the left rear backing plate and drum was a lot hotter than the right side-   via the laser heat gun.    What was happening was that the hot spot would "grab" the brake shoes and tighten up the brakes...............  on just a very light stop while backing-up, like out of the driveway.    The machine shop mgr told me that the drum had a hot spot.   I never could see the hot spot.   I had a replacement drum already turned and about the same size so I put it on the car............... and it drives perfect.          So, I'm not saying that you have a "hot spot"...........  just trying to share with you my solution found after a very long story.    SHalver CLC #24920

[J. Gomez]

J. Rutledge,

Once you have inspected and checked the solutions provided by others above.

If you have the Service Manual make sure you follow the steps on adjusting the brakes under Section 7 page 7-9 â€" 7-10 Major Brake Adjustment.

It is time consuming but it is necessary to performer those to check the clearance on top and bottom of the lining to drum.

Good luck..!

[junkyard junky]

Thanks everyone for all the replies.  Checked the shop manual but I think I had close to the same problem as Scott Halver. Backed the brakes off on that wheel and drove it down the road. Both backing plates and drums were the same temperature. I'm going to get some new brake drums.


J. Rutledge

[walt chomosh #23510]

JY junky,
  I'm surprised no other CLC members suggested the flexable(rubber) brake hose as a source of your problem.(connecting to your backing plate) The hoses deteriorate internally and tend to lock fluid and not return thus causing brake drag. A lot of later model cars also experience this problem.....there have been a lot of brakes burnt up because of drag....walt....tulsa,ok

[D.Yaros]

JY junky,
  I'm surprised no other CLC members suggested the flexable(rubber) brake hose as a source of your problem.(connecting to your backing plate) The hoses deteriorate internally and tend to lock fluid and not return thus causing brake drag. A lot of later model cars also experience this problem.....there have been a lot of brakes burnt up because of drag....walt....tulsa,ok

See Reply #2 in this thread.

[Jon S]

See Reply #2 in this thread.

Reply #3

[Jay Friedman]

I recently had this problem on my '49 when driving it to the GN in Wisconsin.  I never did figure out exactly what it was, but when I returned home a new rear hydraulic hose, a rebuild of the wheel cylinder and then a "major" adjustment fixed it. 

I would especially like to second J. Gomez's advice on doing a major adjustment, which  involves measuring the shoe to drum clearances with a feeler gauge.  It's done a bit differently depending on the year model, so follow the instructions in your car's shop manual.  For example, on my '49 you adjust the shoes by turning the anchor pin eccentric from the back of the backing plate, while on a '55 you tap the backing plate with a hammer.

[J. Gomez]

For example, on my '49 you adjust the shoes by turning the anchor pin eccentric from the back of the backing plate, while on a '55 you tap the backing plate with a hammer.

Jay,

Similar process on the ’56 as for ’55.

A fun afternoon project for sure not so great if you have to do all four wheels and you run out of your favorite "work" motivation beverage..! 

[junkyard junky]

Previous owner installed new wheel cylinder all the way around along with two 2 rubber hoses up front and one in the rear. Right now the car is driveable. I plan on checking everything and adjusting this fall/winter. Right now I'm trying to get a 65 Coronet transmission straighten out after coming back from the transmission shop.