Today Beckie and I took the rare opportunity to leave our kids home and take
a tour through the local mountains with some other members of the Sunbeam
Owners Group of San Diego, ending at a winery for some wine tasting, lunch,
and fun conversation. The Tiger ran flawlessly the whole way, that is up
until about 1/4 mile from home, at which point, following a loud pop, the
brakes went very soft. I limped home and determined the problem was the
hydraulic brake light switch had blown out. I don't know if a similar thing
has happened to any of you, but it did happen to one of the participants at
the Tigers United in Grants Pass in '95, causing him to rear-end another
car. At the time I made a mental note to remove the hydraulic switch and use
a mechanical switch instead. Well, finally, this evening I did just that.
Just take out the Girling switch and replace it with a short 3/8" NF bolt
(don't forget to use the copper gasket) and no more worries. Then, what you
need to do is mount a mechanical switch directly behind (aft of) the brake
pedal arm and adjust it so that it only has continuity (turns on) when you
depress the brake pedal. I like the philosophy of this method over the
hydraulic switch because your brake lights go on even before you have
applied any real braking force, which gives the clown behind you just that
much more time to react.
I took the opportunity to cut open the switch to see how it was constructed.
It consists of a rubber diaphragm, a spring and a copper button that makes
contact with the two terminals. All this is held in place by some kind of
potting material. If I had known how it was built, I probably would have
replaced it sooner. The failure mechanism in my case was a short circuit in
the unit which burned it pretty badly and caused the potting material to
decompose. When I heard the pop and caught a whiff of the smell I was
expecting a shorted cable and was reaching for the kill switch, even before
I tried the brakes. Thankfully, I was going fairly slow up hill, not fast
downhill as I had been doing a lot of earlier in the day.
Sorry for the rant, but I thought some of you might appreciate being warned
of this possibly serious failure potential. BTW, this particular switch is a
replacement I bought from Sunbeam Specialties in 1986. I'm sure that time,
heat, and abuse have played a role.
Cheating death yet again in San Diego,
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