1971 brake problem

[dogpen2]

While running some erands today I stoped to get lunch and when I got back in my fj40 it didn't want to roll. I seemed to drive with the brakes draging or something. The next time I tried to stop no brakes, the pedal was rock hard but had little effect on stoping. As I limped home it didn't get any better. When I did stop I checked the hubs/drums and none seemed real hot. I then jacked each wheel up and three were fine the fourth L/R was just a little tight, it would only go 3/4 revolution by hand. This is a stock 71 brake setup, drums at all four corners. About six months ago I put on a new master cylinder, new wheel cylinders and brakes.
Any suggestions? I tried the search and frequently asked questions but did not find any help.

 

[65swb45]

71 eh? FIrst thing I'd try is disconnecting the brake booster and seeing if it has any effect on the brakes.

Best

Mark A.

 

[2fpower]

flex lines are known to go out and that fits your situation where one wheel is not fully releasing. The theory is that the pressure from the master is enough to push past the colapsed section of the pipe, and gets to the wheel cylinder but as there is no pressure pushing back the fluid it does not fully release.

I had this happen years ago. So, never to step on Marks advice, do what he said first (plus it is free), If that does not work, then replace the flex line.

k

 

[dogpen2]

Ok, disconnected the brake booster vacuumline and no change, it dosen't seem to affect the brake pedal feel either way, also the flex lines are all new and feel solid. Any other suggestions?
Thanks

 

[srgould41]

If the booster being disconnected doesn't make a difference then sounds like it could be bad. I'll let others chime in also.

And to shamefully plug my items for sale I have the booster off my '71 for sale. It works great.

Steve

Ok, disconnected the brake booster vacuumline and no change, it dosen't seem to affect the brake pedal feel either way, also the flex lines are all new and feel solid. Any other suggestions?
Thanks

 

[alb333]

I think you need to take off the drum and have a look at the inner workings.

My front driver side drum brake locked up the other night and wouldn't unlock. So I limped home (about a block away) and when in the driveway I pumped the brake pedal a bunch of times and it came free. I then parked, removed the offending wheel and drum, and found that the shoes had had completely separated/stripped from their metal backing! The shoes plopped out onto the driveway when I pulled the drum off, meanwhile the metal backing was still securely held in place by the springs and cylinders and all else looked fine.

Granted, the whole brake system was shot and I think that wheel was doing most of the stopping work, so I believe it was being unduly stressed. Fortunately, the failure happened on a slow-speed shakedown run inside of my neighborhood -- just in case such a thing happened. All has since been repaired, renewed, and it stops straight and true.

 

[Greenweenie40]

If it was me I would start by pulling the wheels and drums and check all linings and hardwear.