Packard Forum Index » Pre-War (1899-1942)

Greetings All,

I've been having some problems with the RR brake shoes failing to release when I let off the brake pedal. To date, I've replaced the master cylinder, wheel cylinders and brake lines. The brake shoes are in good shape so I did not have them relined.

When I tested the rear brakes, I can move the wheel in the forward direction, but it will lock up if I try to make it go backward. I noticed that the pins that go into the wheel cylinder seem to be getting a lot of resistance when I attached the springs to the point at the center top.

Is it possible that there is too much fluid in the cylinder causing the shoe not to come back to the resting position? I updated to the DOT 5 silicone fluid.

Any thoughts would be greatly appreciated

Gene

How much brake pedal free play do you have?

Also, how old are your brake hoses? The one to the rear may be swelling shut so the fluid has difficulty returning to the master cyl..

You can easily tell if your shoes are not returning: they will not rest on the anchor pin at the top. If you rock the drum back and forth and get movement before hitting a stop, they are not resting on the pin.

Lastly, it is not uncommon that the brake cables have been drawn up too far. This also keeps the shoes from resting on the anchor pin as they should and renders the rear brakes much less effective. Disconnect your cables at the equalizer and make sure you can move them in their sheath. Do a normal brake adjustment at the wheels, then adjust your cables: pull them out of their sheath till all the slack is taken up. Hold them with locking pliers. Adjust the cable ends till you can just get the pins to slide through the clevis.

Have you checked the parking brake cables? I had problems with the rear brakes on one of my cars, it was the rear parking brake cables. I replaced them and and the problems are gone. The cables were stuck, one was frayed, the return springs were weak. They were not fully returning the shoes back to what i will call zero.

I checked them and the cable seemed to return to the rest position. I'll take another look at them to see if the cables are binding up.

Thanks

There still seems to be a fair amount of pedal play. When I bled the brakes, we kept pumping them until there were no bubbles.

Thanks for your help.

I replaced the brake hoses as well. I bought the lines from NAPA which worked fine on the front, but I bought the same line for the rear which I noticed after installation that it is different from the original in that it doesn't snug up tight. I don't have any fluid leaks that I can see at this point.

Thanks