buffalo318

Need some advise guys. I have a '66 AC coupe. Brake lights weren't working and traced it down to the brake light switch. Replaced the switch. Was working but then the brake lights stayed on. Took ac duct apart again and found the plunger in the switch was not hitting the metal bracket to the brake pedal, so the plunger is always out.
The small metal plate with the hole in it, that the switch goes thru is stable, not loose. Appears the switch is going thru the plate straight, and both nuts holding it are secure.
Any suggestions on the best way to properly line-up the switch plunger to the metal brake hardware so the plunger stays in until brake is depressed? Thanks guys.

rongold

Your car must have power brakes, as I don't think standard brake cars have the bracket (striker) you are talking about. Are you saying that the switch wobbles in the hole, even though the nuts are snug, or is the switch striker not hitting the switch plunger squarely ??? I really don't think the switch can wobble with the nuts tight. The striker should be bolted to the pedal and should hit the plunger at a 90 degree angle when the pedal is all the way up. Maybe you have to bend the striker slightly or loosen the bolt and rotate it until it is square (90 degrees) with the plunger, and make sure that the plunger hits the center of the striker. Make sure it is bolted to the pedal securely and cannot rotate. Then adjust the switch so that the brake lights come on when the pedal is depressed about 1/4". Check to make sure that the pedal cannot wobble or move left to right more than about 1/8". If it moves more than that, one or both of the pedal shaft bushings may be worn out. That could cause the plunger to miss the striker.

RON

buffalo318

Thanks Ron. It's not a power brakes car. The switch does not wobble when securely attached to the metal bracket by the two nuts. The switch striker is not hitting the switch plunger squarely. The plunger is very slightly to the left / drivers side of the striker, and facing down very slightly. If I could slightly bend the metal bracket holding the switch I think I could have the plunger more squarely hit the switch striker, but I don't think I'll be able to do that. Cant figure out why this situation has developed. Might try attaching something to the striker so it hits the plunger properly,

JohnZ

Something goofy is going on here - a manual (non-power) brake car doesn't have any sort of striker on the brake pedal arm to engage the stop lamp switch plunger; the aft edge of the brake pedal arm is in constant contact with the switch plunger. There are two holes in the brake pedal arm for the clevis to the master cylinder - manual brakes uses the upper hole and no striker, and power brakes uses the lower hole and a bolt-on striker paddle (using the upper hole) to actuate the stop lamp switch.

buffalo318

Thank you John. I think terminology accounts for the confusion. The switch plunger is not touching brake pedal arm when the brake pedal is not pressed / engaged. It's slightly off to the drivers side of the pedal arm, so the plunger is out and therefore the brake lights are on. Might simply adjust the switch direction as it goes thru the hole in the metal plate that the switch nuts press against so the plunger is in contact with the arm at rest.

66Turnon

I've been having the same brake lamp switch adjustment problem on my '66 coupe. After adjusting the switch location, fore & aft, by loosening the 2 stamped nuts several times, I found the problem was more of a side to side adjustment issue, since the switch plunger was not centered with the brake pedal swing arm. The only way to adjust the side to side location for the switch is to re-bend the mounting bracket for the brake lamp switch, which is welded to the side of pedal sled. To get a clear access to the brake switch bracket, I reluctantly pulled the steering column and the driver's seat. I found this bracket to be kind of wimpy, and with some vice grips, played with it until it was lined up, and then tested the reinstalled switch to ensure it worked before putting everything back together.
Then, a couple weeks later, a neighbor was following me home from a car show and we both banging some gears. Later he told me, every time I hit a gear, my stop lights came on. When I checked the brake lamp switch location, I again saw it was slightly off-center to the brake pedal arm. Also, I can slightly pull back on the brake pedal arm and easily get it an additional 1/8" rearward travel from it. (Tired return spring on pedal sled??)
So I'm thinking it would take some welding to add a reinforcement from the pedal sled to the brake lamp switch mounting bracket to stabilize it, and that probably would require removing the pedal sled from the car to accomplish... which doesn't sound like much fun. So I'm wondering: Wouldn't it just be a whole lot easier to just find a brake pressure activated switch and plumb it into the hydraulic system somewhere. Has anyone tried this on a C2, and if so, where's the easiest location to do this?

buffalo318

66 Turnon-
Interesting post and reading you had the same issues. You were probably as frustrated as I was, Last night I think I resolved the problem, Slightly bent the metal bracket that holds the switch, toward the passenger side since the switch plunger was going to the driver side of the brake pedal arm, so now the plunger is much more centered to the arm. Really snugged the switch nuts to the bracket so hopefully it cant move to the side. Securing the ac duct back in place tomorrow. A lot of aggravation for such a small issue. Good luck.

66Turnon

Buffalo318,
Sounds like we went down the same path to try to resolve this problem. Hopefully you have better results with your adjusted brake lamp switch mounting bracket than I did. When I first looked at the bracket and realized it was aiming the switch plunger off the side of the brake pedal arm, I also noticed it had several scratches on it. So obviously, a prior owner of this car had need to make some adjustments before I came along. I'm beginning to think that the reason this bracket is now so wimpy is that it's been bent so much the metal is stressed. Hopefully yours is a virgin part, and the correction you've made to it lasts. These old vettes certainly weren't made for chubby old guys to work under the dash panel. I want a fix that guarantees I won't have to get under mine again. That 's why I'm hoping someone else has gone to a brake pressure switch activated stop lamp design that I can feed off. Best of luck with your fix, and thanks for the thread!!

Jackfit

66Turnon

Thanks for the reply Jack. In looking at the wimpy bracket problem, your solution is the first to come to come mind for me also, as it keeps everything (the stop lamp control system) basically stock. Were you able to weld the new reinforcement to bracket/pedal sled without removing the pedal sled from the car?

Thanks, Russ

jbthomas

I had the same issue with my 66. The metal was stressed and continued to bend. I made a small end stop bracket with a rubber cushion to limit travel of the brake pedal on return and I added a brake pressure switch in the front brake line below the master cylinder and eliminated the plunger switch. I made the modifications when I removed the pedal assembly to rebuild it with new bushings and spring and wanted it to last. I also rebuilt my steering column at the same time (has to be removed to take out the pedal assembly.

66Turnon

JB,
Thanks for your input. I knew there had to be someone else out there that had considered, or actually gone with, a brake pressure switch to replace the plunger switch. Your location for the pressure switch makes good sense as it is a short distance away from the old switch, and the re-wiring to it should be a simple task.
When modifying the front brake line plumbing to accommodate the pressure switch, did you add a "T" joint off the brake booster and then thread the new switch directly into it? Also, when you removed the pedal assembly (aka sled), what else has to come off besides the steering column? (brake master cylinder, clutch linkage, instrument cluster???) My vette has standard brakes and steering, no AC, so don't have to contend with those added accessories. Rebuilding the pedal assembly while it's out of the car seems like a great idea too. Are the new bushings and springs, needed to do this, readily available? Thanks again for your reply!
Russ

Black_Magic

Tired of trying to get adjusted properly I added pressure switch. Extend the two (2) wires to switch and your done. IIRC it was about 60psi switch???

Painless Wiring 80174

jbthomas

I used a tube fitting tee to splice into the brake line. The master cylinder only requires removing the mounting nuts and the clutch return spring to pull the steering column. Same type pressure switch Blackmagic used and like he said it only requires extending the wires from the plunger switch through the firewall...really easy upgrade and no more worries about whether your brake lights are working or not.

jbthomas

Also the parts needed to rebuild the pedal assembly and the steering column (if needed) are readily available from lots of vendors. LIC, Ecklers, Zips, Corvette America. If you have the column out and you never have removed it I recommend checking the bearing (especially the lower one). Mine was shot and I had no idea it was eating into the steering shaft until I pulled it out. Good as new now.

66Turnon

WOW...Nice looking set-up! That's something else I should be doing: Replacing my prehistoric stock, single well master cylinder with a dual reservoir one. Thanks for your input on the brake pressure switch location!
Russ

66Turnon

JB,
Thanks again for this info. on rebuilding the steering column and pedal assembly. As I previously mentioned, I had the column out once before to get at the mounting bracket for the plunger brake lamp switch. But since I haven't experienced any noise or slop in it, I didn't even consider a rebuild at the time. Now, since it has to come out again to work on the pedal assembly, I will definitely rebuild them both. Thanks for your help and reference as to where to purchase the rebuild parts.
Russ