News:

Due to a technical issue, some recently uploaded pictures have been lost. We are investigating why this happened but the issue has been resolved so that future uploads should be safe.  You can also Modify your post (MORE...) and re-upload the pictures in your post.

Main Menu

Locking up rear brake

Started by hearn, September 23, 2018, 08:37:02 PM

Previous topic - Next topic

0 Members and 1 Guest are viewing this topic.

hearn

My 1954 Cadillac brake is locking up on the right rear.  Does anyone have an idea of what might be the cause.  I'm going in there, but wanted to get some ideas so I could have the parts as I don't have much time on a lift.  Also, days before this occurred, I would lose some pedal occasionally after an hour or so of driving to where I needed to pump the pedal up.  I don't think the two are related, but I don't know.  Any thoughts would be appreciated.  Thanks, Jim

Bobby B

Could be anything, of course. But from your description, my first guess would be that they ARE related. Maybe a slightly leaking wheel cylinder under pressure/ heat, wear, etc. or due to extremely worn shoes your adjustment went to it's Max and now the shoe is either grabbing, cracked, chipped, de-laminating, etc. Once you pull the drum, your answer is right in front of you. No guessing game here with old school brakes. If the car sat for any amount of time, anything is possible with brakes sticking, binding, or acting up. Good Luck!
                             Bobby
1947 Cadillac Series 62 Convertible Coupe
1968 Mustang Convertible
1973 Mustang Convertible
1969 Jaguar E-Type Roadster
1971 Datsun 240Z
1979 H-D FLH

hearn

Thanks.   The car had been driven lately so not a lot of sitting.  Shoes were good and well adjusted.  My guess at this point was the master cylinder leaking internally for the pedal issue and a hose swelling for the lock up.  This time in I plan do do new hoses all around and rebuild all cylinders (wheel and master).  Last time in I did rebuild a couple of wheel cylinder and the others were not weeping at all, but time has past so I'll do they all this time around and replace hoses since I never have.

That was a great thought about the wheel cylinder and for that matter the master cylinder leaking under pressure and heat as both maladies occurred after a hour or more of warm summer driving and the last hour and a half before the lockup was semi-mountain driving.

Bobby B

Quote from: hearn on September 23, 2018, 09:36:04 PM
That was a great thought about the wheel cylinder and for that matter the master cylinder leaking under pressure and heat as both maladies occurred after a hour or more of warm summer driving and the last hour and a half before the lockup was semi-mountain driving.

Jim,
Brake problems sometimes surface when things heat up. Rubber hoses are cheap enough and cheap insurance also when overhauling brakes. Nowadays the metal is so prone to warping that everytime you do front pads on a disc brake car, you need new rotors.
                                                                             Bobby
1947 Cadillac Series 62 Convertible Coupe
1968 Mustang Convertible
1973 Mustang Convertible
1969 Jaguar E-Type Roadster
1971 Datsun 240Z
1979 H-D FLH

Daddio

This may be counter intuitive, but when a single wheel (that was properly adjusted) locks up under braking, it's probably due to the brake shoes on THAT wheel getting soaked in brake fluid.
My guess is a leaky / failed wheel cylinder.
Mike

1956 Thunderbird
SOLD - 1959 Eldorado Biarritz

C Gorgas

I question leaking fluid as cause for lockup. I once had the same problem and it turned out to be the springs. They were weak and could not withstand the heat generated and thus did not perform leaving the brake locked up. I couldn't move the car and feared I would generate a fire from leaking fluid. Just a thought.

tripwire

It might be a leaking axle seal.

Wes in VT
Driving now:
2013 CTS4 Performance Coupe
1940 LaSalle 5229 C4D

A few I used to drive:
1976 Cadillac Ambulance
1969 Cadillac Hearse, Superior Body
1966 Buick Wildcat Hearse
1957 Ford Thunderbird x 3, 1 E code, 2 D code
1956 Oldsmobile Rocket 88 Sedan
1949 Mercury Convertible
1949 Mercury Coupe, Mild Custom
1936 Buick Special Sedan

Jay Friedman

Quote from: hearn on September 23, 2018, 09:36:04 PMThis time in I plan do do new hoses all around and rebuild all cylinders (wheel and master).  Last time in I did rebuild a couple of wheel cylinder and the others were not weeping at all, but time has past so I'll do they all this time around and replace hoses since I never have.

I second the advice from Bobby and C Gorgas.  Besides rebuilding all the cylinders and replacing the hoses, you should also replace all the springs.  These are easily found at a reasonable cost.  Among others, Kanter in NJ sells spring kits.  It's also a good idea to lightly lube with a thin film of white lithium grease all the surfaces (I call them "pads") the shoes contact on the backing plate.

If you find liquid of any kind once the drum is removed, as tripwire suggests make sure you determine whether it's brake fluid or gear oil.
1949 Cadillac 6107 Club Coupe
1932 Ford V8 Phaeton (restored, not a rod).  Sold
Decatur, Georgia
CLC # 3210, since 1984
"If it won't work, get a bigger hammer."

Bob Schuman

Another possible cause is the primary and secondary linings being reversed. The primary lining is the shorter one and always goes toward the front of the car. The secondary is longer and always goes toward the rear. They can be installed the reverse of that, and that was the cause of a locking rear wheel brake on a restored Cadillac I bought.
Bob Schuman, CLC#254
2017 CT6-unsatisfactory (repurchased by GM)
2023 XT5

Jon S

Try backing the star adjuster on that wheel back 4-6 clicks and see if that helps.
Jon

1958 Cadillac Sedan De Ville
1973 Lincoln Continental Coupe
1981 Corvette
2004 Mustang GT

hearn

Thanks for the help.  I ended up going through the entire brake system (while I was at it).  Rebuilt slaves, new master, new arced shoes, new springs, turned drums, and complete purge of old fluid and all new fluid. It turns out that the problem on my lock up was most likely caused by old brake springs.

Bobby B

Quote from: hearn on October 02, 2018, 06:58:24 PM
It turns out that the problem on my lock up was most likely caused by old brake springs.

No one ever thinks to change the hardware when doing a Drum Brake job. I always do now, after a good lesson learned, similar to yours. I'm glad it all worked out and now you have perfect working brakes and peace of mind....
                                                             Bobby
1947 Cadillac Series 62 Convertible Coupe
1968 Mustang Convertible
1973 Mustang Convertible
1969 Jaguar E-Type Roadster
1971 Datsun 240Z
1979 H-D FLH

Jay Friedman

I had a similar problem.  Recently my '49's front brakes started pulling to one side.  I went through them, including changing all the springs.  Never found out exactly what was wrong, but have an inkling it was either a bad hose or bad spring.  Now they stop straight ahead.
1949 Cadillac 6107 Club Coupe
1932 Ford V8 Phaeton (restored, not a rod).  Sold
Decatur, Georgia
CLC # 3210, since 1984
"If it won't work, get a bigger hammer."