"Mechanical" Brake Light Switch (How you mounted)

I mounted my brake light switch in the brake line itself using a "T" the brake light switch screws into the third leg of the T wire it in as normal. As soon as the brakes are applied the pressure pushing thru the line activates the brake lights. No switches to adjust just use a simple two prong brake light switch and mount it wherever the wiring is close. If you want to make a theft deturant devise use a "T" that has a screw valve on it. When its parked get someone to step on the brakes and hold them while you screw the valve shut. It holds brake fluid under pressure in the system holding the brake shoes. Next morning release the valve and everything goes back to normal.

 

Thing is, when that line switch goes out or it takes too long a stroke for it to work. My first one went out and I had to remove, replace and bleed brakes to make sure there was no air in the system. The replacement lasted a little longer, but it didn't activate until my pedal was halfway into a stroke.

With the switch, if it goes out (going on 4 years), I can just swap in another one. No bleeding. Just unplug, remove, replace. The slightest pedal movement activates the brake lights.

 

I too used the mechanical switch because the hydraulic didn't actuate without significant peddle pressure. Simply bolted it to the floor under the car, beside the brake peddle and adjusted the arm so it actuates with very little movement of the peddle. I used the adjustable type, it's worked trouble free for about 15 years.

Here's a couple links:

Adjustable, see photo below:
http://www.gearheadworld.com/store/Universal-Street-Rod-Adjustable-Brake-Light-Switch-P1471.aspx

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Non-Adjustable, See photo below:
http://www.speedwaymotors.com/Unive...e&utm_source=AskAndAnswer&utm_content=Default

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Hope that helps!

 

IMHO, by far the best switch to use is one mounted to the brake pedal bracket inside the car, like modern car's use. I got one from a wrecked late model Poncho. Sorry I don't have pix to share, but an L bracket with a hole is all you need to mount them and they have double nuts to hold them in place once adjusted. And they stay inside the car and dry. Gary

 

Nice setup!

 

I used the complete wiring harness from a c10 pick up because everything is available from just about any auto parts store and I had a few complete ones laying around. Headlight switch, brake light switch, dimmer, turn sig, ignition switch, flasher, and neutral safety switch were all available from all of the three nearest auto part stores. Seemed like a no brainer for me.

 

There are a couple of possible problems with some of the previous switch installations.
One, the plastic GM-style switches designed for interior use are not weather resistant.
Two, these older OE switches will not handle the higher current requirements of modern halogen lights, and will necessitate a brake light relay.
It's better to use a heavier duty switch designed for under floor location, and the SW-42 from Ron Francis is hard to beat, IMO.

 

That Ron Francis switch is a nice unit indeed. It appears however that ebfabman has had his installed for quite some time and he's not reported any problems from having it under the car. Plus, if it ever does fail it's $4.95 at any parts store as opposed to waiting on RF mail order.

Ha ha, my hot rod has no hood, no fenders and no windows - the brake light switch getting wet is the least of my concerns!

 

I don't intend to use halogen brake lights. 1157's have been just fine in my daily driver 72 c10. They should be equally as good in the 50 Merc. The under the floor install could be made weather tight if need be. If the switch goes bad, almost any auto parts store will have a replacement.

 

I use those plastic GM switches under my floor on the outside as well, and never had an issue (on many cars), INCLUDING launching my jet skis with it totally submerged in the lake on the boat ramp.

 

Just a tip: a 2357LL will replace an 1157, & is brighter on the brake filiment. The tail light element is the same wattage

 

Thanks...I will check in to that. I tried the after market LED's and while they were a little brighter on the tail lights, brake light was not as bright. In other words there didn't seem to be much difference between the tail and brake lights. And the price was stupid, like $17 for two. 1157's seemed better. I will look into the 2357LL's

 

Give me a few and I will try to post a pic from my phone if I can figure out how.

 

Finally ......a pic

Posted using the Full Custom H.A.M.B. App!

 

Changed the oil on the Model A today... took a couple photo's of the brake light switch:

 

I mounted mine to the floor so that the arm is riding on the brake lever. Using a 39 pedal style with a Corvette M/C. 1/4 inch movement of the pedal lights the lights. Had a pressure SW but with 4 wheel discs I could stop the car without lighting the lights.

 

great idea. good way to eliminate the "lunge" on a shoebox ford with a starter button.

 

I have one like the adjustable one that Lakeroadster posted. It is in the on position unless tension is placed against the arm, which seems like a backwards way of doing it, and for me makes it difficult to find a way to mount it. Also, it seems that if that little screw that's used to adjust the arm came the slightest bit loose that it would go out of adjustment. Doesn't seem like a very positive way of keeping the arm placed correctly.

 

can someone tell me how the pressure switch that is screwed into the master cylinder is wired up? I believe that the wire goes from the brake lights to one post on the pressure switch, the 2nd post on the pressure switch goes to power. can someone confirm this please.

 

I also used the 55-57 Pontiac switch under the floor with F-1 ford pickup pedals. The switch is made to be in the weather. I simply mounted to switch to the bottom surface of the floor.

 

Mounted under floor of Model A RPU, F-1 pedals.

 

In the past,I have used motorcycle brake light switches. I've also used these switches as a kickdown switch for Turbo 400 transmissions.

 

yes. The switch is normally open when you step on the brakes and get pressure it closes and completes the circuit