Does anyone now where the proportional valve is located on a 1973 ford f100.

 

If your sitting in the truck it will be underneath your feet mounted on the inside of the frame. Just trace your master cylinder lines downward and they go right to it.

 

Basically it's under where the driver sits, tucked up inside the frame rail.

 

Ok well my brake light turns on everytime i turn on my truck. I replaced the master cylinder, and bleed it all around. Brake pedal feels normal but the light still wont turn off. Could it be the proportional valve? Thanks for the help.

 

Did you bench bleed the master cylinder before you installed it? I know you said the pedal feels normal, but two people can have two different definitions of "normal."

If the braking system is in proper order, yet the light is always on, the proportioning valve may not be completely centered. Try slowly pressing and releasing the pedal several times. If that doesn't fix it, then the switch (in the valve itself) could be stuck on or shorted. This all assumes you bench bled the master cylinder. If you didn't, all bets are off.

 

Welcome to FTE

This is a very common problem, and has been...since day one.

C8AZ-2B264-A .. Low Brake Fluid Warning Lamp Switch-threads into Proportioning Valve / Available from Ford and a gazillion autoparts stores.

Applications: 1968/79 F100/350 & Bronco / 1969/79 Econoline / 1968/69 FoMoCo Passenger Cars.

This plastic switch has been a notorious POS since day one. Cracks develop in its threads causing brake fluid to seep out.

When this occurres, the low brake fluid warning lamp on the dash comes on...and stays on!

 

God that truck frame look sweet...

where did you get the power steering box??

g

 

Thanks, the steering box is from Redhead Steering Gear in Seattle, WA.

 

Is it hard to replace the switch that number dummy referenced?

 

No, unplug the switch then unscrew the switch from the proportioning valve. Install in reverse order and bleed the brakes.