I heard that silicon fluid will wreck hydraulic brake light switches. I wanted to run silicon fluid, are there any other options?
Hydraulic switches start only coming on with enough pedal pressure to lock the wheels in a very short time, the rest of the time your brake lights aren't working. You can fit a mechanical '56 Chevy truck switch to just about tnything with a through the floor pedal and a lot of hanging ones too. And they're cheap!
The problem I hear is that the silicone fluid causes the switch to leak. I agree with DrJ, use a mechanical switch, I have never been a fan of those hydraulic switches even with regualr brake fluid.
I too have bad expeariences with hyd brake switches. They don't last long on either fluid. I'm a fan of street works switch. It's very adjustable it's just not cheap. About 20.00 bucks. If you run halogen bulbs they say you should run a relay on any switch.
I replaced all of the hydraulic stop light switches in my heaps with low pressure swithces made by one of the after market wiring companies (I don't remember which one, Painless maybe?). They are more expensive than the $4 switches from Checker/Kragen/AutoZone etc. (they cost about $13), but they are a huge improvment. They work quite well, the brake lights on my '62 Comet, '52 F1 and '48 Fordor light up when the pedal exerts even the slightest pressure on the piston in the master cylinder. Plus they have lasted over 3 years so far, I usually had to replace the cheap ones every 1 1/2 to 2 years. I bought mine at SoCal Speedshop here in Phoenix. I don't know what affect silicon brake fluid woud have on them.
The problem with Sillycone is is is sooooo slippery it works its way past the seals and finally insulates the contacts so they wont complete tthe circuit. As stated, the low pressure switches are they way to go if you are using hyd. Nothing wrong with Mechanical either.
I keep hearing all these tales of the problems with silicone brake fluid, but I put it in my '37 Chevy sedan in 1982 when I rebuilt the whole system and it was in there until I sold the car in 1999. I never had a leak or changed a brake light seitch during that time. I bought a '37 Chevy (OK, I'm in a rut!!) in 1991 and it had been changed to silicone before I got it. I still haven't touched anything on the brake system to date. My '55 Buick & '46 Chevy 1/2-ton will be getting silicone this winter. I swear by it, but that's just my 2¢ ! -Bob
speaking of silicone fluid..We have used it on the last two rods we have built..NO PROBLEMS!!..We have great pedal firmness on the brake and hydraulic clutch systems..no leaks..and NO BLISTERED PAINT around the master cylinder at the firewall. I really dont know why the silicone fluid gets such a bad rap. Dale
I had problems on my 28 delivery so now I use 49-54 chevy switches. They are lever type and just screw them to the floor.
Thanks for the replies. I never figured that a stoopid thing like a brake light swith would cause me this much grief. I think I'll check out those Chev lever switches.
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