Thread: Where did you all mount your brake light switch

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Two ways to do it, either a mechanical switch or an inline pressure switch:

1) Mechanical switch is commonly one like you find under the dash of many cars, actuated by the pedal. Basically, when the pedal is not being depressed, it is resting on the push button of the switch, which is in the "open position" electrically. When you push on the pedal, the button on the switch pops out, causing the switch to close, and the lights go on.

2) Hydraulic inline pressure switch. You insert a Tee into the brake line somewhere (usually near the master cylinder) and when you push the pedal, the same hydraulic pressure that works your wheel cylinders closes the contacts in this inline switch, causing your lights to come on. These switches look similar to the little oil pressure switches you screw into your engine block, except they have 2 tabs for 2 wires.

I've always used the mechanical switch, because I am old fashioned, but we just used one of the hydraulic ones on my Sons '29, and I have to admit it makes a clean installation. We had heard you couldn't use these with silicone brake fluid, as it chews them up in short order, but a vendor at Turkey Run says the newer ones are designed for silicone. (I have had the same silicone brake fluid in my '27 for 12 years, and I will never use anything else, regardless of what some people say about spongy pedal feel, etc.) So we bought one of his switches, and will see how it works in the '29. For a tee, just use one of the "weatherhead" types you can pick up at any auto store.

If you decide to go with one of the mechanical ones, all you have to do is fab up a little bracket to hold the switch against the pedal, so that it releases when you push the pedal down.

Hope this helps.