Brake light comes on for a sec. then goes off

[DARTHV6]

Hello Folks,
My brake light comes on when I press the brake, then goes right off. I don't have much peddle and I can't panic stop. I changed out the power master long time ago. The car has been siting for about 15 years and I only drive it once a year. I'm ready to drive it now but I'm getting rid of a bunch of kinks! I bled the brakes yesterday with the same problem. I'm going out today to get new calipers and brakes because It's time to change those anyway. I have S-10 calipers on the rear and a line lock on the front. That's all I can remember I've done to the car.

Any idea why the brake light comes on and why the brakes are bad?

Thanks much!
Art

 

[313badbuick]

Hello Folks,
My brake light comes on when I press the brake, then goes right off. I don't have much peddle and I can't panic stop. I changed out the power master long time ago. The car has been siting for about 15 years and I only drive it once a year. I'm ready to drive it now but I'm getting rid of a bunch of kinks! I bled the brakes yesterday with the same problem. I'm going out today to get new calipers and brakes because It's time to change those anyway. I have S-10 calipers on the rear and a line lock on the front. That's all I can remember I've done to the car.

Any idea why the brake light comes on and why the brakes are bad?

Thanks much!
Art

You changed out the pm for vacuum brakes. Could possibly be the master cylinder going bad

Sent from my SM-G955U using Tapatalk

 

[DARTHV6]

You changed out the pm for vacuum brakes. Could possibly be the master cylinder going bad

Sent from my SM-G955U using Tapatalk

I did change that about 20 years ago. If it's going bad, it wouldn't be from over use cuz I don't drive it much but now I want to drive it, it starts messing up!

I just ffinished bleeding the brakes for a fourth time and I still have the same problem. I did notice like an air sound coming from the master cylinder when I pumped the brakes. I don't think that's supposed to happen.

 

[MaxVO2]

*****It sounds like the master cylinder seals have gone bad if you hear hissing inside and the cylinder. If you end up rebuilding or replacing it might be a good time to get a new proportioning valve as well since you will have to bleed everything again anyway. My valve went bad and no amount of bleeding would help it. I had improper brake line pressure on two wheels. I also run S-10 cylinders on my GN. Ironically I still have the original powermaster but have replaced the accumulator bowl a couple of times. I do bleed the brakes every couple of years though.

 

[DARTHV6]

Ironically I still have the original powermaster but have replaced the accumulator bowl a couple of times. I do bleed the brakes every couple of years though.

MaxV02,
I made a mistake, I didn't replace my powermaster, I only replaced my accumulator bowl once, a long time ago. Would a bad accumulator bowl cause this?
I'll re-post this with the right information so I won't confuse everybody...

 

[MaxVO2]

****Yes. A bad accumulator bowl can cause that exact symptom you mention (brake light coming on for a second or so.) Kirban sells the bowls and perhaps other vendors as well. I would not recommend buying a used bowl, just buy the new one and be done with it. Brakes are too important to cheap out on as it's a safety issue. It's a very easy fix if that is your only problem.

If the switch on the top is going bad, the powermaster motor sometimes just runs almost continuously, which can burn it out. If it's just the light problem as you mentioned, it sounds like it's just the bowl.


Good luck

 

[DARTHV6]

****Yes. A bad accumulator bowl can cause that exact symptom you mention (brake light coming on for a second or so.) Kirban sells the bowls and perhaps other vendors as well. I would not recommend buying a used bowl, just buy the new one and be done with it. Brakes are too important to cheap out on as it's a safety issue. It's a very easy fix if that is your only problem.

If the switch on the top is going bad, the powermaster motor sometimes just runs almost continuously, which can burn it out. If it's just the light problem as you mentioned, it sounds like it's just the bowl.


Good luck

I think You are right. The light comes on for just a second and goes off. I looked for leaks everywhere and couldn't find any. I bled the brakes with two different people and couldn't find any air. I'm hoping for a very easy fix this time! I'll start with an accumulator bowl. Probably could use one in time anyway.
Thanks for the hint,
Art

 

[CenTexT-Type]

Any updates? I changed out my Accumulator also with the same symptoms as you. It fixed the problem, like having a new Powermaster, great brakes! A few months later the switch burned out and blew the fuse(no brakes, thank goodness i was just cruising and not racing). If you are keeping the Powermaster, I recommend replacing the switch too as a preventive measure for piece of mind.

 

[DARTHV6]

Any updates? If you are keeping the Powermaster, I recommend replacing the switch too as a preventive measure for piece of mind.

No GOOD updates. I replaced all the brakes, cylinders and calipers. Brake light went off but brakes still soft. I just want to hold 5 pounds of boost at the line. I changed the switch years ago

 

[gsgnnut]

You don't want to hear this but I'm going to tell you any way. Your power disaster is toast from sitting. Time to replace with vacuum or hydroboost. Don't waste time on it just swap it out. Otherwise it will find a way to kill you.

 

[DARTHV6]

You don't want to hear this but I'm going to tell you any way. Your power disaster is toast from sitting. Time to replace with vacuum or hydroboost. Don't waste time on it just swap it out. Otherwise it will find a way to kill you.

I agree. The worst thing we can do to these cars is let them sit