I had both front calipers installed and new brake pads put on my mint condition 1985 Nissan 200SX a month ago. When I take my car out for a drive after a while (10 miles or so) both break pads start sticking and smoking and I have to floor the gas to get the car home. I have checked and both are well lubercated. Now I have to replace the brake pads cause the heat is making them turn to dust. Could this problem be the master cylinder that I had installed about 7 years ago? Also, a few months ago I accidentally put about 3 tablespoons of power steering fluid in the master cylinder reservoir by accident but I thought I got it all out. Let me know your thoughts on this mess. Thank you for your time.
That heat could also boil your brake fluid, damage your flex lines, and I’d be amazed if your rotors were not already destroyed. I strongly urge you not to drive this vehicle until the problem gets resolved. It’s unsafe.
Were the calipers replaced a month ago because the old ones too were sticking?
I hate to say it, but you may have just proven beyond a doubt that PS fluid in the brake system CAN damage brake system seals. However it IS possible that it’s your flex lines that have borne the damage.
All I can tell you is to have it towed to a reputable shop, tell him the entire story, and let him go through the system with a fine tooth comb.
Who helped them escape?
Sometimes I can’t help myself
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I’d start with a new master cylinder and complete brake fluid flush…and pray…
Power steering fluid (oil) will cause the piston seals in the master cylinder to swell blocking the fluid return hole. Fluid pressure held in the brake lines will increase as the brake parts get hotter, you have witnessed the results.
Replace the master cylinder and flush the old brake fluid out.
The problem might be with the brake hoses going to the calipers.
These hoses can deteriorate internally where the rubber can act like a check valve.
That is, you apply the brakes and the pads make contact with the rotors. But when the brakes are released the pads remain in contact with the rotors.
One way to check for this is, pump the brake pedal several times. Then see if the rotors rotate freely. If not, open the bleeder screws. If brake fluid shoots out of the bleeders, and the rotors then rotate freely, suspect the brake hoses.
Tester
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I think Tester’s guess is more likely than a bad MC. Replace the MC too if you like in the process, and obviously check to make sure the new calipers are the correct models for your car and installed correctly and the slides are sliding; but I think the problem is the flexible brake hoses that lead to the calipers.
Power steering fluid probably isn’t such a good idea in the brake lines, but whether that is what caused the rubber in the flexible brake lines to deteriorate, hard to say. On an 85 pretty much any rubber part has to be suspect. Nice looking vehicle btw. I think you’ll be back on the road in no time. Possibly with a bunch of brake stuff replaced, and maybe new rotors too. Not that big of deal.
Should add, when brake fluid is contaminated by oils, sometimes the only solution is to replace all the rubber-type parts and seals. Once oil gets into those seals, it causes them to swell and twist and it never comes back out.
I agree with Tester. I’ve heard this and it sounded far-fetched to me, until I had the exact same thing happen to me in an old F150. Apply brakes, fluid pressure comes in, but won’t go out. It seemed to happen (to me) mainly when hot, so a “cold check” didn’t show anything. I waited until symptoms presented, then opened a bleeder…hot fluid sprayed out everywhere!
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