89 Front brake issue...
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From: Lynden, WA.
89 Front brake issue...
The pedal seems to return, but the front brakes hang. This vehicle has been sitting for the last year or so. It drives well otherwise.
Where do I start? Pedal pressure does not fade, and the power assist seems fine. The rear brakes don't seem to be hanging at all.
Calipers, master cylinder, booster? How do I check each? If the booster was leaking, then I'd figure there would be other engine run characteristics indicating a vaccume leak. Pedal pressue is consistant, so I don't suspect the master cylinder.
Do the calipers have return springs? Or is that in the master cylinder?
-Steve
Where do I start? Pedal pressure does not fade, and the power assist seems fine. The rear brakes don't seem to be hanging at all.
Calipers, master cylinder, booster? How do I check each? If the booster was leaking, then I'd figure there would be other engine run characteristics indicating a vaccume leak. Pedal pressue is consistant, so I don't suspect the master cylinder.
Do the calipers have return springs? Or is that in the master cylinder?
-Steve
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From: Lexington Mo
I'd most likely start with getting a good look at the brake caliper's and hoses. Does the piston in the caliper return into the caliper easy, or is it taking alot of force (sticking piston). Is the hardware for the caliper letting the caliper move back and fourth? Do the brake hoses look cracked, can you see the inner hose anywhere?
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That's kinda where I was heading first. Externally, the hoses look 'fine'. So I guess it's time to pull the calipers off. I might as well change them out as long as I'm going to take them apart.
Before that, If I pull the booster vacume line, drive without power assist, and the brakes do/don't stick, then I could suspect or rule out the booster. Right?
If the hoses were soft, then wouldn't I feel that spunginess in the pedal? Even when the brakes are stuck on, there's no fade in the pedal at all.
-Steve
Before that, If I pull the booster vacume line, drive without power assist, and the brakes do/don't stick, then I could suspect or rule out the booster. Right?
If the hoses were soft, then wouldn't I feel that spunginess in the pedal? Even when the brakes are stuck on, there's no fade in the pedal at all.
-Steve
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From: Lexington Mo
The way I've allway's checked the vacume booster is to pump the brake pedal until it is a hard pedal (engine not running). Hold pressure down on the brake pedal and start the engine. When the engine is running, the brake pedal should fall some. If not then you either have a bad booster, or no vacume.
For what new calipers and hoses cost anymore, I'd sure look tht way. If the piston's are hard to push back in. When you install you're new parts, use something like Hi-Temp anti seeze. Only where the caliper needs to slide back and fourth. Don't get that stuff on you're brake pads.
Bob
For what new calipers and hoses cost anymore, I'd sure look tht way. If the piston's are hard to push back in. When you install you're new parts, use something like Hi-Temp anti seeze. Only where the caliper needs to slide back and fourth. Don't get that stuff on you're brake pads.
Bob
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From: Atlanta GA
BIIs are known for having brake piston issues, it could have had it before it was parked.
One way to test the hoses is to set the brake pedal with a stick between the pedal and the seat so the brakes are on hard. Then look to see if the hoses have visible bumps or bulges.
I would replace the pistons and hoses (you will find taking off the pass. fender the easiest way to do the hose clip) and bleed the whole system.
One way to test the hoses is to set the brake pedal with a stick between the pedal and the seat so the brakes are on hard. Then look to see if the hoses have visible bumps or bulges.
I would replace the pistons and hoses (you will find taking off the pass. fender the easiest way to do the hose clip) and bleed the whole system.
Tuned
Joined: May 2004
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Not saying this is your problem, but I would for sure change the brake hoses. Reason being, I have an 89, and my hoses started leaking at the crimps. I thought this was odd, because the hoses looked perfectly good. Just my opinion. Are you saying your front brakes are locked up without the brakes being applied?
Tommy J
Tommy J
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From: Lynden, WA.
No. The front brakes aren't locked up without applying the brakes.
It happens after using them a few times enough to slow down from highway speeds. Then they 'stick on'. Eventually the pressure bleads off then it'll roll agian.
-Steve
It happens after using them a few times enough to slow down from highway speeds. Then they 'stick on'. Eventually the pressure bleads off then it'll roll agian.
-Steve
