I've owned my project car for about 2 years and the brake lights have never worked, it's the last thing I need to fix to pass inspection. The car is a 71 Mach 1 with manual drum brakes, I already jumped the switch with a paper clip and the brake lights came on, so it's either a bad switch or maybe the wrong one? The switch has been replaced sometime before I bought the car, in the pictures, the silver one is the old one I took off, the gold one I got from O'reillys today. They're made opposite and I don't know which one is correct. The silver one was installed with the U shaped side cover to the outside, I had to loosen the master cylinder, so I could unhook the MC pushrod, in order to get the old switch out. Also there was only one white plastic washer on the pin. Shouldn't there be two? And is there a bushing that takes the slop out of the MC push rod connection? I'm guessing the side of the switch that has the U, faces down, and goes closest to the brake pedal?
I need help with 71 brake light switch install
3X2GTO
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I've owned my project car for about 2 years and the brake lights have never worked, it's the last thing I need to fix to pass inspection. The car is a 71 Mach 1 with manual drum brakes, I already jumped the switch with a paper clip and the brake lights came on, so it's either a bad switch or maybe the wrong one? The switch has been replaced sometime before I bought the car, in the pictures, the silver one is the old one I took off, the gold one I got from O'reillys today. They're made opposite and I don't know which one is correct. The silver one was installed with the U shaped side cover to the outside, I had to loosen the master cylinder, so I could unhook the MC pushrod, in order to get the old switch out. Also there was only one white plastic washer on the pin. Shouldn't there be two? And is there a bushing that takes the slop out of the MC push rod connection? I'm guessing the side of the switch that has the U, faces down, and goes closest to the brake pedal?
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The u shaped side should be closest to the brake pedal arm. IIRC there should be 2 plastic washers, 1 to the inside, 1 on the outside after the MC push rod.
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The thing you need to understand about the brake light switch is: when released, it's on. When engaged, it's off, meaning, if the pedal is up, it presses the switch in and shuts the lights off. As soon as you press the pedal, the switch pulls out and makes the connection and the lights turn on.
You might just need to adjust the switch position.
You might just need to adjust the switch position.
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With the rod on the pedal stud, slide the rod left just enough to slip the switch up onto the rod and pin, into final position. So in thinking that process thru, the upen U should face up.
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Nope, it's a "Normally Open" switch. Note the pix below and the metal "lever" in red. Note how the lever is slightly bowed in the center, and how the brake pedal pushrod is squared on the end. The spring in the switch keeps it in the "off" position. When you push on the pedal, the resistance of the pushrod depresses the switch and completes the circuit. The black bushing must be present in the center hole of the pushrod and the white bushings on either side. Also of note is the brake light switch spring which is different between manual and power brake applications.
1966 Convertible, Nightmist Blue, currently has 250 I6, T5, 3:1 open diff
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Here's a drawing from the MPC that shows how it's supposed to be. Yes, there's a bushing that goes in the master cylinder rod and two nylon washers. I recently replaced my switch and the one I got from OReilly didn't work out of the box. I had to fiddle with it. I'd try getting the bushing and washers, then put your original back in to see if it works.
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I was wondering how manual and power differed, let's hope the correct spring is put in at the time of assembly.
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I don't what happened there, it posted before I was done, well here I go again. A little brake light follow up, hopefully it'll help some poor soul down the road. I received the new brake switch, washers and bushing from WCC, everything looked and fit well, but it took an extreme amount of pedal pressure before the brake lights would come on, I repeated this numerous times, still not working right. With the lights not coming on as the car was stopping, I could see being rear ended, so I took out the new Scott Drake switch and bent the tab just a hair, well it never worked again. I then ordered a new, correct Echlin MANUAL brake switch # SL207 from NAPA, went to pick it up and it was reversed from what I needed,( just like the original defective switch that started all of this) I then ordered another switch from NAPA, this time Echlin #SL238 for POWER brakes ( mine are manual) It came in today, had the correct orientation, just got it installed and the brake lights come on using normal pedal pressure, they work as new. I have no idea why the manual switches wouldn't work with my manual brakes. I'm guessing the power brakes switches have a lighter spring in them? The most simple job, and counting travel time, I bet I have 4-5 hours in it!
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