Brake Light Issue

[trip]

Hey Everyone

I have an 1987 Buick Grand National, and buddy and I replaced all the lines in the car as I blew out a wheel cylinder a couple years back. The repairs are all done and we went about bleeding the car as per instructions that were on turbobuick.com. The pedal seems good, and there are no leaks

The bleeders were opened and closed numerous times so all the air is out of the system. Now the issue that occurs is the brake light on the dash comes on when the pedal is pressed to brake. As soon as the pedal is de pressed the light goes off. I figured the brake stop light switch was sticking. That's not the case.

I have read that the accumulator ball can fault and cause this issue. I just don't want to start throwing parts and not solving the issue.

If anyone has some experience with this please let me know

Thanks

 

[earlbrown]

You did make sure the fluid is still topped off after filling the accumulator, right?

That's normally the accumulator getting weak. One pump lowers the pressure below the idiot light's threshold and as soon as the pump fires up, it replaced the pressure and the light goes out.

 

[trip]

Hello

By meaning the accumulator, that's the bowl off the side of the master cylinder? I wasn't supposed to prime the bowl or anything

The fluid reservoir was topped up numerous times during the bleeding procedure.

Thanks for your input

 

[earlbrown]

Yes the black ball. It had a bladder in it backed up my mucho pounds of pressurized gas. When you first turned the key on, the motor pumped braked fluid into that ball and the level in the reservoir drops accordingly. As they age, the pressurized gas leaks out, pressure drops and you get less and less 'pump of the brake pedal' before the motor has to cycle. The light starts to blink when you start getting close to one or two pumps.

To set the fluid level correctly, you have to leave the key off and pump the braked until the pedal runs out of assist THEN top off the fluid.

 

[trip]

Thanks for the good info, I will attempt this before looking for a new setup. I did move the car and the pedal is feeling good. Cheers