brake lights staying on?

[gbhrps]

Gentlemen,
Strange one here. Recently, my 2 year old 55 restoration has taken to putting its brake lights on, overnight when parked in the garage. Twice in the last week I've noticed the brake lights on when taking out the garbage. I pumped the brakes and they go out. Several hours later, just to be sure they stayed out, I went to the garage again and they were on once more. Pump the brakes once and out they go. After 2 days of this, I'm not taking any more chances and I've cut the battery juice with my quick disconnect. Now, since this system uses a pressure switch on the frame inside the engine compartment, and not on the brake pedal assembly, I'm of the opinion that the return spring in my brake pedal assembly isn't quite doing its job. Am I right? Anyone have a similar problem and solved it?

 

[tbird5866]

When you determine that the problem is not the brake pedal return spring, which would not be original equipment, replace the brake light switch. If you are using silicone fluid, I understand these switches do not last long.

 

[gbhrps]

Harley,
Do I understand you to mean that there is no return spring on the brake pedal? That the spring assembly in the master cylinder returns the pedal? And yes, I originally had silicone brake fluid in the system for a short time. Must I replace the brake light switch and stay with the regular brake fluid, or is there a switch available that will work with silicone? Many thanks in advance!

 

[gbhrps]

Gentlemen,
I changed the brake light switch today and kept the standard brake fluid. The brake lights appear to be working just fine at present, but I'll keep an eye on them. Curiously, the old switch has a leaking corrosion around the metal head where the plastic insert for the switch terminals are located. Did the silicone brake fluid corrupt the switch inerds and allow the fluid to leak past its seal?

 

[nomadbird]

There has been long standing controversy regarding pressure type brake light switches compatibility with silicon brake fluid. Some say there is no way silicon fluid can cause failure. I happen to be in the camp that says: "If you use silicon brake fluid, carry a spare brake switch". There is a switch available from Ron Francis Wiring specifically for use with silicon fluid. I've heard this is not guaranteed fool-proof either. So far, the best solution seems to be the mechanical switch conversion kit available from CASCO.

 

[bjwardsd]

I had the same problem with my '57 T Bird. It turned out that the brake master cylinder was bad and would maintain pressure on the brake system, mostly when the system was hot. It woudl dim than go bright than dim than go bright for hours than it would finally go out. I replaced my master brake cylinder and the problem went away. I have silicon brake fluid and never replaced the brake light switch, just the master cylinder.

 

[scoopieb]

There has been long standing controversy regarding pressure type brake light switches compatibility with silicon brake fluid. Some say there is no way silicon fluid can cause failure. I happen to be in the camp that says: "If you use silicon brake fluid, carry a spare brake switch". There is a switch available from Ron Francis Wiring specifically for use with silicon fluid. I've heard this is not guaranteed fool-proof either. So far, the best solution seems to be the mechanical switch conversion kit available from CASCO.

Any idea where I can get the CASCO switch?
thanks,
steve

 

[Jimz Bird]

Here is a link to the switch:
http://www.parts123.com/parts123/yb...~S36R0BDS8A46317575214a~Z5Z5Z5~Z5Z5Z50000219a

and the main site:

CASCO Thunderbird Parts

Download the pdf catalog - lots of good stuff and they have a newsletter also.

HTH

Jim