BRAKE ISSUE

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Apr 24, 2014 | 05:09 PM

F-250 restorer

Thread Starter

Lead Driver

Joined: Mar 2008

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From: Near Los Angeles

BRAKE ISSUE

Hello all:

While doing my disc conversion some time back I made the ultimate mistake: in a rush, getting dark, had to finish, and put p/s fluid in the master! I have since replaced the master and all the soft lines, not to mention the rear calipers.

My problem now is the rear right caliper gets higher psi in the fluid lines than the left. It locks up when the left does not. When I bleed them I can see the force of the fluid coming out is less on the left side. Both calipers and soft lines are new. Both get their fluid from one line until the junction block, which is brass. How can fluid be metered differently?

Apr 24, 2014 | 05:14 PM

co425

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Joined: Oct 2010

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Clog or pinch in your driver side rear line? Sticking piston in that caliper?

Apr 25, 2014 | 05:34 PM

F-250 restorer

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Lead Driver

Joined: Mar 2008

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From: Near Los Angeles

I went through the system and checked the lines for flow. I have good flow at both sides, and good stream when bleeding. Good piston movement. Drive test and the rear passenger side locks up and the driver side rear does not. I'm quite baffled.

Apr 26, 2014 | 12:12 AM

VocaTexas

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Joined: Feb 2009

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When you mix power steering fluid and DOT 3 you get a thick gel. It will totally stop up a brake system. You may end up having to replace your steel lines and prop valve to solve your problem.

I had to have an entire brake system replaced when a kid at a service station put power steering fluid into the brake system on a vehicle my (now)ex-wife was driving.

Jul 9, 2014 | 12:41 AM

jbancroft

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Joined: Sep 2012

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ditto. your screwed. Did the same thing, but "after dark" isn't my excuse

. replace all the lines & cylinders. anywhere that cocktail of P/S and brake fluid was, you have to replace. I guess you could try flushing it out with a solvent, but what solvent dissolves a P/s brake fluid cocktail- acetone? MEK?

Jul 9, 2014 | 09:29 AM

F-250 restorer

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Lead Driver

Joined: Mar 2008

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From: Near Los Angeles

That has to be the single most expensive mistake I've made on any vehicle. I never thought I'd have to replace the steel lines, but at this point I'll do anything to make it right.

Thanks to all. k

Jul 9, 2014 | 10:03 PM

dittohead

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Joined: Jan 2009

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From: Courtenay, B.C.

If it was my truck i would unhook all the lines and spray brakeclean backed up with shop air. There is no reason to replace the hardlines but the soft lines and possibly the calipers wont be useable.