Have any you guy had problems with your brake switch. Its new but I have the old single style master cylinder. and the hydraulic fluid type brake switch.
I have installed 4 new,diffrent brands of stop light switches and none of the work like they should. After install each one, the brake lights are off,until I pump the brake. Then the brake lights stay on. And to get them to go off I have to remove the wires. With the to wires off and apart,the lights are off,then touching them,they are on. Which is normal. But what the deal with the switches. I was wondering,do brake light switches come with diffrent pressure settings. Just now I was thinkin,wonding if the guys at the parts house were giving me oil pressure switches. They look alike. I figure maybe one of you had a idea. Or a switch part number for me to try. It seen like to me with just what little pressures on the lines its makin the lights stay on.
THANKS !

 

Ford part number: C1AZ-13480-A Stop Light Switch

I have no idea where autoparts stores stoplight switches are made, but I wouldn't be surprised of it was China. One cause of faulty stoplight switches is old dirty brake fluid plugs them up. It is after all a pressure switch.

 

Are you sure that your linkage is completely releasing the M/C when you take your foot off? There needs to be play in it, no pressure on the M/C piston.

 

I have also heard that the stock switches corrode easily over time and the a Harley-Davidson brake switch will work. I got mine from Sac Vintage Ford and haven't had any problems but I put a new MC in also.

 

Could a 10 psi residual pressure valve in the system cause the stop lights to stay on like this?

 

Here's my best guess: The problem is not with the switches; it is very unlikely that all four are defective. The most likely problem is that the adjustable pushrod on your brake linkage is adjusted too long. This will not allow the check valve inside the master cylinder to release pressure even when the brake pedal is fully disengaged. Try adjusting the pushrod for MORE freeplay, and see if this doesn't solve your problem. Good luck.

 

I agree with the post above. I had a similar problem with my 58. The lights wouldn't come on until I was almost at a complete stop. I installed an electric switch from an '84 Olds 88. I just removed the bumpstop from the brake pedal and used the hole to mount the switch. Still works like a charm and it's been 7 years. Just run the wires through the firewall and leave the pressure switch disconnected. Good luck, John

 

When I needed a new stoplight switch for my 50 (back in 99) I walked into Auto Zone and picked one up, put it in and it's worked perfectly ever since (and I used my truck as a daily driver until 04). I've heard of some folks having problems with the pressure switches, but it hasn't been my experirence.

An oil pressure switch would close the circuit when you let off the brakes, and open it (turn the brake lights off) when you pushed the brakes, so they'd work opposite of what they're supposed to...not like what you're experiencing.

Try adjusting the pushrod as M6 said, and make sure you have a return spring pulling the brake pedal off of the pushrod (from the linkage to the frame). This will help your brake pedal come up, improving the function of your brake system all around. Likewise, make sure that there isn't a bunch of crud in your MC/Brake system.