Powersteering to Break Reservoir!!

[rms1390]

So my friend has a 1993 5spd 240sx hatchback, and put some "POWER STEERING" fluid to the brake reservoir and drove it for a little over 10 miles. Now he is freaking out because we were under the hood and pointed out the right place where the powersteering fluid was suppose to go. Now he doesn't know what to do and what issues he could of caused to the break system. Please if you have any suggestions or what issues he could of caused let me know. Thanks!

[Chaluska]

just do a brake fluid flush.. open the bleeders and let all the fluid come out, fill, bleed, repeat until fresh fluid comes out... shouldnt be a problem.. brake fluid is more corrosive than power steering fluid

[Mark13marcos]

Yeah a fluis flush will work perfect make sure to purge everithing right!

[rms1390]

Thanks guys, I will make sure to let him know all this and to do evrything right. This outta calm him down a bit! Haha.

[Razi]

I'd use those little suction hand pumps from Autozone to get all the fluid out of the reservoir, so you pump as little PS fluid through the lines as possible.

[mechanicalmoron]

I could be totally wrong, but I don't think there will be any serious problem, though obviously it should be fixed. I'd say do like razi said and pump out the reservoir, and then refill it with clean fluid and (using the pump you'll already have) flush the individual lines. Brake fluid is nasty stuff, I don't think PS fluid takes off paint or anything, I think the only real problem would be viscosity, but it should still probably be flushed.

[IanS]

just do a brake fluid flush.. open the bleeders and let all the fluid come out, fill, bleed, repeat until fresh fluid comes out... shouldnt be a problem.. brake fluid is more corrosive than power steering fluid

It's a much bigger problem then you think, trust me.

pS fluid is petroleum based, while brake fluid is glycol based. The rubber portions of the braking system are specifically designed to stand up to long term exposure to glycol. They are not designed to come into contact with petroleum. When the 2 are mixed, the petroleum will cause all the rubber in the system to swell. You would be amazed how often people make this mistake. I see it every other month or so.

Get the fluid out now, preferably directly from the reservoir to start with. Don't push any more through the system then you have too, though I am sad to say the damage is likely already done.

When I see this at work, it's all or nothing. Everything with rubber gets replaced. The master cylinder, the brake hoses, the calipers/wheel cylinders, as well as the pro portioning valves on some vehicles.

Even if you flush the system now, chances are problems will show up down the road. The hoses leading to the calipers will collapse first, causing the calipers to stay on, then the calipers will start to leak. Around the same time the master will start behaving poorly and the pro portioning valve may act up.

You may have gotten lucky, and the fluid hasn't worked its way too far past the master. Personally I don't like to gamble with something as important as the brakes.