brake warning light/ distribution switch

[jimp]

When I push the brake pedal down while bleeding and it gets near the floor the warning light comes on. I have installed a new (rebuilt) master cylinder, carefully bench bled it, both according to my 73 Chevrolet Service Manual instructions which says to tilt the m/c nose down and nose up while pushing in the piston, and level as per the m/c replacement instructions. When I bled the calipers I get only a small amount of fluid from the rear bleeders (2 in each) compared to the fronts.

When I tried the brakes in my drive the fronts, as expected, lock up.The pedal has some resistance going down and firms up near the floor and locks up the fronts. I have tried different bleeding sequences-front/rear without getting the darned light to stay out! (No, it is not the parking brake)

I sure hope I don't have to replace the switch because it looks like a typical plumbing job that gets worse as you get into it! Help!! How Do I Reset This Switch???

 

[bill81vette]

1st Welcome to CAC!!
in what order did you bleed the brakes?
there is a certain order to bleed them RT Rr,Lt rr,Rt ft lt ft.

 

[Peer81]

And the rear has two nippels on them both

Greetings Peter

 

[6880 Mike]

The chassis service manual says to begin with the left rear inner. They probably have their reasons for this. I usually begin with the right rear inner and have never had problems going this way.

RR inner
RR outer
LR inner
LR outer
Right front
Left front.

 

[jimp]

thanks 6880 mike & bill81vette

Since you guys agree on a proper sequence I will try bleeding again with a confident heart. I am using the hi-tech way of having my wife pump the pedal for me, being sure that she now pushes the brake pedal and not the gas pedal. I couldn't figure out why I wasn't getting any fluid or bubbles out the first time I asked her for help.

 

[6880 Mike]

...I couldn't figure out why I wasn't getting any fluid or bubbles out the first time I asked her for help...

Since she is doing you a big favor by helping out, gently remind her to keep the pedal down until you tell her to let it up.

Not to overstate the obvious, but you're going to owe her more than you already do.

 

[jimp]

bill81vette & 6880 mike

Thanks a bunch guys!
I now have a good brake pedal and 4 wheel brakes AND NO WARNING LIGHT!!
I initially followed the directions in my '73 GM published service manual that I have used as my bible for all the years. It says to start at the master cylinder and proceed to the nearest wheel then the next nearest and so on. It did not get rid of the light but the sequence you guys provided got rid of that infernal light! Thanks again.

 

[GTR1999]

As you probably know, the light comes on when there is a pressure differential, there is nothing more then a spool that shifts position and makes the dash light switch. So that in case you loose one circuit, ie the front brakes, the light will come on as a warning- 60's technology.

I found the best tool to bled vette brakes is the Motive Tool. Man I wish I thought of that years ago, I would be retired now.

 

[jimp]

motive bleeding tool

Thanks GTR1999, but I hope I am done bleeding brakes. I only last year replaced the original rotors and I am real careful replacing pads so I don't lose fluid. I guess I use the gas pedal more than the brake pedal.