Stuck brakes

[Chris Stewart]

Ok, washed the Bravada and got ready for the long overdue "keep'er loosened up" cruise.
Took it to the end of the road and after slowing down and turning around, the front brakes didn't release. After working the steering wheel side to side, it loosened up a little but after hitting the brakes again, they stuck again.
Rascal's started heating up too.
After taking each wheel & caliper off and changing the dirty fluid by pumping the brake pedal, pushing the caliper piston out then opening the bleeder and pushing the piston back into the caliper then closing the bleeder then pumping them up again a coupla more times until the fluid cleared up, I went for another test ride, the front brakes were still staying applied.

What would you do next?





__________________
1992 Bravada, 190K, stock
1997 Bravada, 101K, stock...was "called away"

[FishFind]

get new calipers

[gmtech1]

Is there any chance the brake fluid was contaminated? Is the rubber seal on the master cylinder cap swollen?

[ericn1300]

Strange to have both calipers locking up, maybe something with the anti lock brake speed sensors, I hear they have a problem with rusting on older GM's. How many miles on it now Chris, ours is going over 250K before the year is out and it's still a daily driver.

[Chris Stewart]

I forgot to add, the brakes were dragging enough that I thought engine power was down due to low fuel pressure or something else.

Turns out both front brake lines were severely restricted. The passenger side was so stopped up I couldn't even blow through it. The hoses were kinda soft/buggered up right next to the bracket that bolts on to the upper a-frame.
When I took them loose from the calipers, they didn't drip any fluid.
Installed new lines from the local chain type auto parts store & problem fixed. Near $12 each.

It just turned over 191000 Eric.
I haven't checked to see what they're stopped up with. I don't think it would've happened if I'd drove it more often.
Your's is still driven daily?
Have you done the timing chain yet?

__________________
1992 Bravada, 190K, stock
1997 Bravada, 101K, stock...was "called away"

[aleekat]

What typically happens, the hose breaks down separating. When you apply pressure, the fluid flows to the calibers, then when you let off, the parts of the hose separating drops down and blocks the flow back to master cyclinder. Sort of a one way check valve.

[ericn1300]

Nice fix Chris, I might just have to change out the brake hoses on the next brake job. I was planning on replacing the rotors ($30 ea) and the calipers ($12 ea) anyways since they are original and have almost 250k on them. My son is in his third semester in auto shop so I'll have them do it and they get the mechanics discount on parts too.

I haven't done the timing chain, didn't know it was a concern. The Bravada is still both a daily driver and our long trip vehicle of choice. Took it camping and off roading a few times this summer and planning on a winter drive of over 1500k miles thru snow and ice over a 7,800 foot pass for Christmas. Just hope we don't end up like the Donner Party.

[Chris Stewart]

Thanks aleecat, that is the way the driver's side acted. You could just barely blow a tiny bit of air one direction but none the other.
The passenger side was just stopped up...I guess the high pressure from the vacuum assist master cylinder managed to get some past the restriction.
It's easy to take brakes for granted but after some trouble, it is very nice to have the normal brakes now.

I chickened out on the timing chain & sprocket at 180K Eric. It's a true double roller chain and was still in very good shape...maybe 1/4" droop when you hold the chain sideways so's the links & pins are vertical.

How about transfer case & differential fluids? I haven't changed those out either but I'd done the transmission a few years ago and pull 1 qt. out then add 1 qt. new yearly...stays nice and bright red too.

I'm driving it a bit, maybe through the winter because the tires are showing some weather checking and they have less than 5000 miles since new. Any tricks for healing them?

__________________
1992 Bravada, 190K, stock
1997 Bravada, 101K, stock...was "called away"

[ericn1300]

The weather checking is actual caused by UV rays in the sunlight. Use protection like Armour All, it might help swell it up a bit but I don't think it reverse the damage, just stop it and put some cardboard or plywood to cover the tires while it's in storage. The RV shops sell tire tents for storing those babies, they have the same problem.

[Chris Stewart]

Thanks Eric. I see they have a non-shiny dressing/protectant nowadays.
The clearcoat on the wheels is looking dismal too. Do you think the wheel clear coat is urethane?

[ericn1300]

Are they the OEM wheels? If so I'm in need of a rocket center logo on my spare, I'm sure you don't need all of yours. I covered it up with a laminated picture of Rodney Dangerfield in a disc for now.

The problem with refinishing wheels is getting them clean first. The wheel and hubcap shop here in town uses an acid bath followed by a good power washing. If you can get it clean enough and take off all the flaking clear cover a coat of Wipe On Poly brand (polyurethane) will actually clean up the discolored spots in the urethane. Easy stuff to use, just pour some on a soft cloth and wipe it on, no runs or brush marks.

[Chris Stewart]

Thanks Eric.
All my rockets are looking poor. Maybe someone has them on eBay.
Did your's have one on the spare? Mine doesn't but it's mounted inside. Yours is hung outside, right?

[ericn1300]

Originally Posted by Chris Stewart

Thanks Eric.
All my rockets are looking poor. Maybe someone has them on eBay.
Did your's have one on the spare? Mine doesn't but it's mounted inside. Yours is hung outside, right?

Yep, mines hanging on the back with a picture of cross eyed Rodney staring down the tailgaters until I can find a rocket. I have a matched spare that is in rotation with the other four, every 5k miles with the LOF. The front tires have to come off every 5k to lube the front end, 13 zerts I believe. I carry a full size spare because I actually use the Bravada off road and for long distance trips. I've needed to use it three times so far. For all of you with an outside spare that's not in rotation, be sure to loosen and tighten the lug nuts on every rotation anyway to make sure they don't freeze up on you when you need them most.