88/89 XR4 Brakes

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Larry H
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88/89 XR4 Brakes

Post by Larry H » Tue Mar 05, 2019 4:24 pm

Brake pedal has a tendency to travel near the floor! Obviously this isn't good...I can't locate any fluid leaks. And the brake light in the dash flashes.
What's the issue? M/C, booster, or......
any input appreciated
Larry with Five XR4s and Two Scorpios

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Re: 88/89 XR4 Brakes

Post by John Brennan » Tue Mar 05, 2019 4:52 pm

First, thoroughly bleed the brakes to ensure no air has entered the system. If that checks out, and with no leaks, you probably have a bad MC. Check with our vendors (see main page).
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Re: 88/89 XR4 Brakes

Post by andyofcolumbusmerkur » Tue Mar 05, 2019 7:11 pm

I had brake fluid "hide" in the rear suspension on an xr. Leaked out of the braided hose which was rubbing under full compression. Also had fluid hide out inside the brake booster on a ford taurus. No drips really and couldn't figure out why the level was going down. If the car still seems to stop I would guess back brake system. You could cap off each half at the mc one at a time, and see how the pedal feels.
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Re: 88/89 XR4 Brakes

Post by merkurdriver » Wed Mar 06, 2019 4:34 am

Agreed - if no trapped air, and no external leaks, then probably a bad master cylinder.

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Re: 88/89 XR4 Brakes

Post by DPDISXR4Ti » Sat Mar 16, 2019 11:36 am

merkurdriver wrote:
Wed Mar 06, 2019 4:34 am
Agreed - if no trapped air, and no external leaks, then probably a bad master cylinder.
What Mike said. :withstupid

You'll probably find all your lost brake fluid inside the brake booster.

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Re: 88/89 XR4 Brakes

Post by Andy82GT » Sat Mar 16, 2019 5:04 pm

I had same issue - ended up being MC internal seals were shot, causing spongy pedal/pedal to the floor. Like suggested, check for leaks at all brake line connections, then bleed brakes starting at furthest wheel. If still bad, good luck finding a rebuilt MC. DONT GET A USED ONE!
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