I am having a problem with my brake light staying on after i drive the car for a while. I just rebuilt the master cylinder but i'm still having the problem. I picked up a universal pressure switch but it was nothing like the one on it. Its a 53 coronet with original 6volt system. Does anyone know where to find a pressure switch that will work for it, or have any other suggestions.
I ussually use a mechanical switch on the brake pedal itself GM G body ones are fairly compact and easy to mount. Pressure switches are normally only used to set off the idiot light when the braking system is low.
It's funny that this comes up. My Dad just found out he had a bad pressure switch after his brake lights wouldn't come on! He tried replacing everything from the bulbs to the light wiring in the steering column! He didn't think it was the pressure switch since it was new, and showed 12 volts in and out when he tested it with a meter. After he spent several hundered dollars, and several sleepless nights trying to find the problem, I again told him to replace the pressure switch(which I had done previously) and volia! The brake lights worked! I told him I'd had the same problem with my coupe, so I was sure that's what he needed. So after all the money and time, it ended up being an $8 part, that took 5 minutes to replace! After experiencing all this, I would follow Greezeball's lead, and put in a MECHANICAL switch!!
Check your brake push rod to master cylinder clearance. You must have free play or the system will build pressure over multiple braking exents and your brake lights will remain on.
X 3 on the mechanical switch...My 54 had the same prob. The car was entirely new from boosters to brakes, wires and all. I kept changing pressure switches and was going to find a low pressure switch until I found out that most every late model car is mechanical now adays. Under 10 bucks and mounts in short time. GO MECHANICAL!!! Good Luck
You can use any type of switch, micro, lever, push ****on......its how you can mount it on your pedal ***embly. And it won't leak.
if you want to use a pressure switch, get one from the harley shop, they last a lot longer than the ones you get from the flaps. they cost a bit more but you wont have to change it for a lifetime.
58 chevy came with a simple mechanical switch i'd recomend going back to one, they never fail check out lmctruck or brothers
I also prefer a lever type ( not pressure type ) brake light switch. Your vehicle being a 6 volt system means you nee to find a lever type for 6 volts. I KNOW that the 52/53 Cadillacs had this type switch. 1952/1953 Chevrolets also. I would venture to guess that the Buicks, Olds, and Pontiacs had the same type. It would be real easy to fabricate it into working ... trouble free.
I think the mechanical plunger type GM switches are best. They were used on millions of GM cars and trucks, are easy to install and adjust.
I had a problem with extreme pressure used to activate my pressure switch in a fenderless coupe. Ron Francis made a low pressure switch and in 6 years, haven't had a problem. If your brake lights are staying on, you may have a problem with the brake fluid heating up. My coupe's m/c is next to the exhaust pipe so I had this problem. I used a heat shield designed for a starter to keep the m/c cool.
you are building pressure somewhere air in the line or your push rod is'nt letting your fluid back. yes you may have hot fluid. you have to fix what is causing this issue before you change out the brake lits switch. then when its fixed why change the light switch?. they work well!
To the best of my knowledge, none of these switches, pressure or mechanical, is voltage sensitive. There only contacts inside, no coils. Ray
Yes a basic micro switch could be made to work just as long as the contacts are rated for the current draw of the lights.
Any car I've ever built I've always used mechanical switches - just seemed easier and I will continue to do so - however - I've driven cars for years and years with pressure switches that never gave me a moments trouble & it's actually kinda nice that they show you if pressure is building without you noticing. I second the notion that if you're gonna run one - get a GOOD one!!
When the brake pedal is released, make sure there is a little free play between the push rod and the piston in the master cylinder. If you have power brakes it is possible the valve in hte servo is malfunctioning.
also if there is a reliev port in the bottom of the reservoir, make sure it is clean and allows fluid to return when the pedal is released.
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