Contaminated brake system

[rainman1]

Well I have a question about the ABS module. My bonehead son put powersteering fluid in my brake system. Of course the master cylinder has now failed and I'm replacing everything in the system. My question is whether or not to replace the ABS module? Are there any rubber components in the system that would have been damaged by the powersteering fluid? Can I just flush out the unit with new brake fluid and expect everything to be fine? My concern is putting it back into the system and then have it contaminate the new system. Any thoughts on this?

 

[CDW6212R]

Well how much was the truck driven that way? How much use has the ABS system seen? If the answer is none or extremely little, you might be fine to just bleed it all out with a new master cylinder. The fluid has two paths that it can take through the ABS module. The bypass(normal) path may not be hurt at all by power steering fluid. I wouldn't want to guess how sensitive the ABS valving is to the PS fluid.

That ABS module cannot be bled completely manually. You can bleed fluid through normally, but only the bypass path will be bled out. You definately need to have it bled with the special Ford tool, because air will enter the ABS module as soon as the master cylinder is removed. Only that tool can bleed the ABS, it manually cycles the pump.

Personally I would bleed it well with about a quart of high quality fluid. Don't bleed any through until removing the master cylinder. Don't worry about air, because you will have to have it bled specially anyway. Bleed it manually first, then test it, then have it bled thoroughly again by a Ford tool. I would price used ABS modules, and plan to buy one if needed. If the truck is a critical(only vehicle), I would soon buy an ABS module as a spare. If not I'd just be ready to buy one. Your ABS pump may not be hurt yet. Good luck,

 

[BrooklynBay]

Welcome to this forum! I would suggest that you flush out the old fluid, and refill everything with brake fluid before you start to replace any components. In comparison, brake fluid is much harsher, so I don't think the P/S fluid could have damaged everything. Brake fluid is strong enough to remove paint. Some scanners are capable of cycling the ABS solenoids.

 

[CDW6212R]

I suggested pulling the master cylinder first from "Of course the master cylinder has now failed" first post statement. You want as much of the contaminated fluid out before it reaches the ABS module, and only about half can be sucked out the top of the master cylinder. If nothing had yet failed I would also first bleed it well, and keep an eye on it closely.