Hey everyone

I really need help. My younger brother accidentally put power steering fluid in the brake master cylinder and didn't tell me because he didn't think much of it. He told me he didn't put much. The other day he was driving and all of sudden the rear brakes started locking up. We let the car sit for a bit and the rear brakes eventually stopped locking and we drove the car home. I talked to a mechanic and he told me I need to change out the brake master cylinder since the rubber has expanded and flush the brake system. This is what I'm planning to do but my friends dad suggested me to rebuild everything in my brake system since any rubber component might have expanded and eventually my brakes could eventually fail. And if i plan to rebuild the calipers does anyone know where i can get 99spec rebuilds. Any advice would really help.

 

The first thing to do is make your brother suck out the system with a straw! I might be wrong but isn't brake fluid more prone to swelling rubber than steering fluid. Becouse of the cost i would bleed and flush the whole system and try it first. But thats just me i might be wrong and its your *** on the line!

 

Just flush the system with brake fluid.

 

Because it's your brake system, I wouldn't recommend taking the cheap route. I don't know the detains of what PS fluid can do to a brake system, but if it's anything as bad as what they are saying, I wouldn't run the risk.

I've always been of the opinion that if you can't pay to maintain your brakes, then you might as well sell the whole car.

Also, be glad he didn't put gear oil in the crank case...then things could have been really expensive.

 

Thanks for the responses everyone. My friends dad told me that his friend that me that one of his friends put transmission fluid in brake system and eventually the brakes completely stopped working. Thats why he's suggesting me to change out all the rubber pieces.

 

power steering fluid will eat almost anything thats rubber, and eventually your brakes will fail and you dont want to be driving when they do.

 

What he said ^^^

What have we learned from this? Never let someone else do maintenance to your car unless you unfailingly trust their judgment. I lost a motor to my brother, but you could have lost more than that.

 

i dont understand if power steering fluid eats rubber. WOULDN'T THE "RUBBER" HOSE THAT CONNECTS TO OUR POWER STEERING RESOVOIR BE METAL FROM FACTORY?. my stock pwr steering rubber hose is still running strong from 94

 

gasoline eats plastic, yet the FPD and FPR are both made of plastic. My guess would be either the rubber is a support and the actual hose is made of something different or they used a different rubber compound for those hose to make it resist the corrosion o the PS fluid.

 

this is why i dont let my family touch my FD... EVER.

they may sit in the passenger seat and thats it.

 

When different fluids get mixed up, they become like mazout and clog the system

 

Actually mine are both metal. And at least in the case of the FPD... with what I assume is some type of rubber diaphram.

I'd follow the the recommendations of the OP's mechanic. I'd also ask him about the ABS assembly.

 

First off, do you know if it was standard Power Steering fluid or ATF? The FD uses Dexron II standard which is basically ATF. If he put ATF in, I can't really see that doing a lot of damage.

I would flush the system with some cheap DOT brake fluid twice and then see what happens. Just drive it around your neighborhood a few times and/or go to an open parking lot to do some 40 to 0 hard stops. That will let you know if you are good to go or not.

However, the first thing you should have done when you found out about it was drain it immediately, not post here on the forum. The longer you leave it in, the more harm it could possibly do..

 

http://www.herguth.com/capabilities/brakeswell.htm

 

This IS %100 true.... All your rubber brake lines, caliper piston O-rings, master cylinder O-rings, ABS O-rings and any other rubber material in your brake system WILL fail. Ask yourself a question: Which of the two can you wash away with water? The answer is brake fluid. Power steering, ATF, oil, grease and wd-40 are all oil based and WILL cause failure to your brake system no matter how much it's "flushed" out. If anyone has ever rebuilt brake calipers or read directions on "how to" would know that you NEVER use an oil based fluid to lube during the install of the O-rings. The best thing to lube them is the brake fluid itself.

If that were my car I would be replacing EVERY rubber component in the braking system.
-J

 

YEP

I have all the parts you need so if you'd like a good price send me a PM

 

Just flush the system and you be fine.

 

My brother put standard power steering fluid. My rack and pinion had a leak and just had it replaced about a month ago. So i have been driving w/ the power steering fluid for about a 1000 miles already now too.

 

Sorry for the confusion I don't have any 99 spec brake parts.

Good luck with this

 

Take your car to a good brake shop, and have them power bleed the entire system. Ask them if a small amount of PS fluid will do any damage. I doubt if it will have caused any harm.

Make your brother pay the bill.

 

How confident are you in that statement? I bet you wouldn't put power steering fluid in your master cylinder, drive it for 2-3 days and then "flush" it...
-J

 

After reading the fluid reaction articale i would change all the rubber parts. The hospital or worse is not a good option, the flush might work for awhile then when you need the brakes the most it blows a seal or line. Its good there are people who know what there talking about!

 

Sorry to hear this.

Something similar happened to my Miata. (I didn't do it)

The brakes eventually got so tight I had to park it until I had time to work on it.
Top speed in 4th gear at this time was 45mph because the seals in the calipers had swollen so much.

Regarding replacing the MC, sorry again, that is not enough.

Here's what I replaced:

Master Cylinder
All 4 calipers (the rubber seals were shot)
Proportioning valve
Replaced rubber lines with new SS lines.

Cleaned out all hard lines (twice) with brake cleaner. I bought a gallon jug.

I mechanic friend of mine knows someone who's brakes locked up on the freeway because of this. One of the quick lube chains (forget which one) had an employee that dumped the wrong stuff in her MC.

They had to pay for the expensive brake job.

My mechanic first looked at the Miata for me and told me what had happened. Unfortunately there was no way for me to find out how this happened and who did it.

Sorry to be the bearer of bad news, but any components of the brake system with rubber parts in them need replaced.

 

Make sure to replace the clutch master and slave cylinder internal components. I think they also share the same reservoir? Come to think about this, it could really be a very serious problem should the brakes lock up along with the clutch at the same time?

Sorry to hear an FD driver going through so much pain in resolving problems created by someone else.

I think there should be a warning label on the refill container.

 

Hey guys,
I just joined the forum to learn a little something about rx7s.
Was just going to lurk for a while and do some reading when I came across this thread.

Just want to say something to those of you that suggested to "just flush" the system.
All of you should NOT be giving advice like that when you know nothing about what you are saying. People's lives depend on a well functioning braking system.

quick lube places around me are not allowed to even check ps/brake/clutch fluid levels for that reason.