Rear brakes locked up!

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LuckyLobo
Posts: 1
Joined: Fri Mar 27, 2015 6:11 pm
Location: Montana

Rear brakes locked up!

Postby LuckyLobo » Fri Mar 27, 2015 6:25 pm

I try very hard to look through the forums first, before wasting any time. I can't find the answer to my problem. Today, out of the blue, I drove my 1989 BII XLT three miles down the road. At times, I have noticed my rear brakes sticking a bit. I try to not use my emergency brake, because it old and it does have a tendency to stick. The cables are old. I was mostly fine, until I stopped to get my mail, 1/4 down the road at my box. I started up and backed out and noticed a lot of pressure, like the back brakes were on. I drove forward for a bit and had to pull over to make sure I didn't the e brake pushed down a bit. it was not. I turned off the engine again to chat with a friend. I started back up to drive home and could not move. I tried reverse and forward, to see if they would break loose. I had to put it in 4x4 low and in first gear just to get it to the end of the driveway. That was it! I got underneath to check the ebrake cable. it was limp. I took a hammer and smacked the drums. Both back wheels are locked up! I tried again, in 4x4 low to rock back and forth with no luck. Very strange that this would happen at the snap of a finger. Could this be an ABS failure of some sort? What can I check? I did find an electrical connection that was dangling down behind the ebrake pedal, but maybe it's always been disconnected. Thought? Things to check? I'm dead in the water and live in the middle of nowhere with no mechanics, at all.

Tom

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tekatlarge
Posts: 951
Joined: Tue Jan 17, 2006 8:54 am
Location: Kent, Worshington

Re: Rear brakes locked up!

Postby tekatlarge » Sat Mar 28, 2015 11:07 am

It sounds like you have a classic case of collapsed rubber brake line. As it is rear brakes only I would guess it is the rubber flexible line from the chassis to the rear diff housing.

To release the brakes to roll the vehicle all you need to do is loosen the bleeder screws on both rear brakes and relieve the pressure built up.

The rubber flexible brake lines are put together with basically a tube in a tube. The inner tube will leak after a time with age and flexing. When you put your foot on the breaks the pressure from the Master Cylinder flows into the wheel cylinder. in a leak situation the pressure leaks from the inner line into the hose lining. the pressure builds by repeated applications of brakes. when enough fluid gets between the inner hose and lining the pressure squeezes the line closed. when the brake is released the lining pressure stays and will not allow the fluid to return to the master cylinder. This keeps the brakes locked.

You will need to replace the flexible line and now would be a good time to replace all 3 flexible hoses. The two front lines probably are ready to go bad by now also.

I hope this helps you out..
The Tek @ Large
Kent,Worshington
I was borne under a rock. So what's your excuse?

rayrayd
Posts: 17
Joined: Mon Aug 04, 2014 8:17 pm
Location: Carriere, MS

Re: Rear brakes locked up!

Postby rayrayd » Mon Mar 30, 2015 12:06 pm

Good call Tek I think you hit that one on the nose! I would bet borrowed money that is the problem.

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tekatlarge
Posts: 951
Joined: Tue Jan 17, 2006 8:54 am
Location: Kent, Worshington

Re: Rear brakes locked up!

Postby tekatlarge » Tue Mar 31, 2015 1:04 pm

Thanks
The Tek @ Large
Kent,Worshington
I was borne under a rock. So what's your excuse?


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