One Brake Not Releasing, Others Are Fine

[CMS]

Ok, I drove my truck home a few months ago and half way home the drivers side rear hub was locked up, so on the side of the highway my brother and I pulled the tires off and eventually decided to just bleed the brake to see if that would fix it... The brake released and off we went. After we got home we ordered the parts for a complete brake rebuild minus the air pack.

Last week I went through the system, flushed the lines with alcohol, rebuilt every cylinder as well as the master cylider(which was amazingly clean) put new Dot 5 in the truck etc... I drove it around the block and when I got home the same rear drivers side hub was hot, non of the rest are even close to its temp. The pads are backed off of the drum all of the way and it still gets hot. The return spring is on there as well.

Does anyone have an idea? I am supposed to take it on a trip on friday...

Thanks

 

[Sundance]

Check the rubber brake hoses sometimes they will swell and clog allowing pressurized fluid in but not out.

 

[littlebob]

I know a soft rubber line can cause it on some vehicles, it acts as a check valve.
Hope this helps.

 

[Flyingvan911]

How about the wheel bearings? It may sound like a strange suggestion but is it possible?

 

[littlebob]

How about the wheel bearings? It may sound like a strange suggestion but is it possible?

I wouldn't rule out anything, if they were worn or loose enough to let the drum tilt on the axle it could do it.

 

[CMS]

I used compressed air to blow out all of the lines prior to adding new fluid and if the rubber hose to the rear axle was swollen closed, wouldnt both sides be sticking? ( on my truck one rubber hose feeds a tee that splits the fluid to two copper lines, one going to each tire). I didnt see anything wrong with the bearing when I took it out and re-packed it, but that is a very valid thing to check.

Also does anyone know what distance the shoes are supposed to be from the drum and could this brake be closer to the drum than the rest causing it to come in contact with the its drum before the others?

 

[cattlerepairman]

Also does anyone know what distance the shoes are supposed to be from the drum and could this brake be closer to the drum than the rest causing it to come in contact with the its drum before the others?

I had to play with my left front brake because of the same symptoms. You need to use a feeler gauge, remove the inspection cover from the brake drum, and check that you have 0.02" (0.5mm) on top and 0.1" (0.25mm) at the bottom and a gap all along the brake shoes. Check the values in the TM to be sure.

Sometimes the brake shoes have a slightly different curve than the brake drum and, while you have a gap on MOST of the shoe, it can still touch the drum somewhere (for me, it was at the very top). I find that even a little contact heats up the drum significantly.
Therefore, the method one uses on a car (tighten brake shoes while turning wheel and back off a little once they start grinding) does not reliably work on the Deuce.

 

[808pants]

If this happens again, one diagnostic method might be to crack open OTHER bleed valves in sequence, starting at front, to see for sure whether there's pressure anywhere else in the system - thus ensuring it really isn't that common rear hose acting as if a check-valve - though as you say, you'd expect it to keep pressure more or less evenly on both rear drums (could be mechanical factors that would bias the trapped brake pressure to the one side if it's not quite high enough).

(and you don't really mean "copper lines" behind the rubber, right?)

--dave

 

[Warthog]

The Tech Manuals cover how to adjust the brakes. There is a Minor and Major adjustment.

I would lean towards the bearings being bad on that wheel.