I'm running a stock Master Cylinder with the original style pressure switch for the brake lights. I have had to replace the switch three times in under three months. Has anyone else had this problem?
I wouldn't think that the amperage is too high on the contacts, since my truck is 12 volt (half the current/twice the volts).
I just drove Athens to Savannah and back (500 miles R/T)overnight to see my dad, who just had surgery, and drove most of the way home with no brake lights.
The switches are only about $5 at NAPA and relatively easy to change, but it's frustrating.

 

Nope, mine still has the original '52 piece. Are you sure it's the switch, and not the wires near the switch? Maybe when you are changing out the switch it temporarily fixes a bad connection. I haven't replaced three brake light switches in 40+ yrs, there's something else wrong. What application is the NAPA part for?

 

Could they possibly be giving you a 6V switch instead of a 12V?

 

Since I have not yet driven my 1954 F250, I don't have personal experience, but I have read that these switches can be unreliable. When I wired up my lights, I used a 12V relay to carry the current to the brake lights. The only amps going through the brake light switch are what is required to close the relay. I am hoping this setup proves reliable. Maybe next sprign I will get to find out.

 

Hey Ross!
The switch is for a '51 Ford Truck (when I ask for it at the NAPA counter this is what I get)
I had my wife operate the brake pedal and I checked continuity through the switch with an ohm meter.....nothing. Put on a new switch and there go the lights. I have voltage to the switch and have run all new wires for the entire circuit. I guess this is what you get with parts made who knows where.

 

Well, I wonder if you can still buy them at Ford dealers? Sounds like they used them for a long time if NAPA still carries them. It sure ain't rocket science to make a simple switch. I hope NAPA is covering them under a warranty?? Regardless, driving without brakes lights is a sure way to get rear-ended!!

 

They were used up to '67 on the pickups.

 

I've heard they don't last long if you are using DOT 5 brake fluid.

 

That sounds odd, but I'll check and see what I'm using in the brake system.

 

I also had problems with my truck eating brake switches at an alarming rate. My best solution so far was to flush the system completely with new brake fluid after a piece meal rebuild of the brake system. However, I keep an extra switch in the glove box. You would be amazed how fast the switch can be replaced if you practice enough.

 

Are you sure it is an electrical problem? I lost my brake lights and went thru 2 new switches before I found out the switches were fine (finally checked continuity with ampmeter). The problem was insufficient pressure from my master cylinder. I thouroughly cleaned and then rebuilt master cylinder but to no avail. I went to a local parts store to find an electrical switch to replace my old pressure switch. The parts gentleman agreed to provide a switch or he said he could tell me how to fix my current setup. I asked how to fix what I already had. He provided mw with a "T" with compression fittings on two ends and a threaded fitting for my stop switch on the 3rd outlet. He told me to splice this directly into one of my brake lines and I would have sufficient pressure to activate the switch. Worked like a charm. Just my experience. May help you or someone else.

Hump

 

I like that idea of a tee for the pressure switch! If you put it in the right place it will receive boosted pressure. Even better. I will do that the next time I need to replace mine. Thanks.

 

NEVER use compression fittings on brake line as it can cause a failure.

 

if the aplication is for a 51 ford than the switch is probly 6v instead of 12v. I too installed a relay and as of yet have not had any problems.

 

Are you using a hydrovac? or remote booster? I don't see how the pressure would be any different otherwise.

FOR SURE -- NO compression fittings!! Hardware store brass fittings are also likely to be suspect.