Ford Bronco Brake Problems

FORD BRONCO
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MARK HOAG
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1988, Ford Bronco, 351, 4x4, 170,000. Brake pedal goes to the floor when it is running and feel like no brake, when the engine is off I have good brakes pressure. the abs light stray on?
Jun 23, 2007 at 10:43 AM
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MERLIN2021
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Any fluid loss? and I think the ABS on your truck is rear only...
Jun 23, 2007 at 3:16 PM
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MARK HOAG
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no fluid loss. How do I turn the ABs off to see if it the problem
Jun 23, 2007 at 10:18 PM
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JWALTH02
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I had this same problem with my 92 351w bronco. The people I bought it from had power steering fluid in the brake master cylinder. All I did was replace the master cylinder and flush the brake lines with new fluid, basically giving me a pint of mud. So what you're saying sounds like my seals going out in the master cylinder roughly $50-60 at autozone. But before replacing that I'd take off a tire and have someone push the brake pedal as you loosen the bleeder fitting on your front caliper (easiest) to see if you're getting fluid. If you don't I'd go ahead and replace the master cylinder then flush your brakes.
Jun 24, 2007 at 6:58 AM
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MARK HOAG
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wife push the brake pedal as i loosen the bleeder fitting on both front caliper, was getting fluid. right front pass. side had a lots of air in the line. bleed all the lines got some of the pedal back , when you turn it on, i lost the pedal it goes on the down to the floor , but when it off I get it back?
Jun 24, 2007 at 7:14 AM
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JWALTH02
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Ya this sounds exactly like my problem, the seals going bad and there's no rebuild kit. I had pressure when it was off, but then I had to drive it five miles to the nearest autozone to get the part with no brakes. Interesting experience to say the least. You're gonna need to take the old one with you cause they had a reman and it was back-asswards and wouldn't fit so I had to buy a brand new one.
Jun 24, 2007 at 7:20 AM
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MARK HOAG
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Thank you, will try
Jun 24, 2007 at 7:26 AM
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JWALTH02
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Cool. Just be sure to flush and bleed your lines cause you don't want any air in the system cause that would be bad. Though now that I think about it I would, before buying anything (well a bottle of brake fluid) go through an bleed ALL your lines. When your wife pushes the brakes open the fitting, then close BEFORE she lets off cause that'll just suck air back in. Try that first and make sure all the air's out then see if it fixes the problem if not then it's deffinitly the master cylinder.
Jun 24, 2007 at 7:32 AM
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MERLIN2021
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If you have a contaminted system take some fluid from the master and put it in some water...you will see either a whits milky fluid or white milky fluid with oil beads in it...if you have oil beads the recomendation is to change ALL rubber parts and flush lies with alcohol! If the test is ok change master...
Jun 24, 2007 at 8:48 AM
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MARK HOAG
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its help a little, still have a lot of play in the pedal
Jun 24, 2007 at 11:32 AM
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JWALTH02
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Did you try what merlin said? Put some of your fluid in water?
Jun 24, 2007 at 5:04 PM
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MARK HOAG
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Change the master , flush out the system, there is a hiss when i push the brake pedal when on, when off a have alot of pedal,
Jul 1, 2007 at 12:17 PM
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MERLIN2021
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Still did not answer contamination problem...IS THERE OIL IN MASTER???? 2 Different answers depending on yours!!!
Jul 1, 2007 at 12:48 PM
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MARK HOAG
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No oil in system , brake fluid is clear, going to rebled lines again, I think it the ABS, when I unplug it the pedal was hard as a rock when the engine is off, when on, goes to the floor
Jul 1, 2007 at 3:27 PM
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