Brake Problem

If my Jeep sits overnight when I go to move it the brakes are locked. No my foot is not on the brake pedal. The first time it happened I thought it was from the shoes being frozen to the the drum but last night the temperature was in the 50's and it did it. I have to rock it back and forth to get them to release. After that they work fine.

 

shoe's in backwards:?

 

collapsed brake line acting like a check valve?

 

I had that happen once with a m-38. It turned out to be the vent hole on the master cylinder was plugged.

 

All new brake lines installed last summer which at the same time the brakes were upgraded to 11". I'll check the master cylinder cap vent hole.

 

When was the last time you pulled the drums off? Sometimes the dust and moist air kind of rusts (not the right word but as close as I can find!) the shoe to the drum. I had the same problem I pulled the drums and you could see where the shoe was bonding to the drum. Put new shoes on turned the drums and problem went away.

 

If I remember correctly, and I might not, the vent hole was not in the cap but in the main body of the master cylinder. This might not be your problem, but thats what mine was, brakes locked on after sitting for a while. I dont even remember if it was called a vent hole in the manual (I have lost my manual). I mistakenly loaned someone all my jeep books, and I will never see them again. But have a close look at the entire master cylinder.

 

Thanks for your input. The drums were turned before I put them on the Jeep and I've put about 600 miles on the whole thing. I'm also thinking that this might be caused by the master cylinder going after all its the original one. I plan on checking to see if any brake fluid has leaked out of the MC thinking that one of the drums might be wet and causing the shoes to stick to the drums.

 

You could also check the backing plates to see if the pads that the shoes ride on are groved and are holding the shoes against the drum.