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TR2/3/3A TR3 break light switch.

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Don Elliott said:
When mine stopped working, I bought two new ones. I checked that they both worked by using my compressed air nozzle and a continuity checker to see that they switched when I applied the air pressure. They both worked at about 30 - 35 psi air pressure. I put one in and it was good for 5 years. Then it failed so I re-tested the new spare I had in my tool box for 5 years. It wouldn't work even at 110 psi. So I chucked it in a lathe and turned it to find out why. There is a disc about the size of a dime that closes the contact. It was black with oxidation which I assume must have developed over that 5 year period.
I don't know why they don't use stainless steel for that disc.
Don
Click to expand...
I bought a pressure switch from Napa today, they had one on the shelf, box looked old stock. I hooked up a regulator and a pressure gauge then checked the pressure needed to close the circuit, it was 75-80 PSI!!!
That is way to high!
Probably oxidation like Don said!

I returned the switch.
I will order one from TRF and hopefully it will connect at 35-40PSI.
I guess that any brake switch would work as long as it has an 1/8 NPT thread with spade terminals.
Randall, mentioned an early Ford switch?
Part #_______________
Nothing is ever easy!
Lyle
 
TruCraft said:
Randall, mentioned an early Ford switch?
Part #_______________
Click to expand...
Sorry, Lyle, I have no idea. Since it didn't work out, I did not try to save the part number or application.

Maybe someone else knows.
 
I will order one from TRF.
Will let you know what pressure the switch connects at.
I need a few other things anyways.
All the little things are taking longer than expected.....darn Murphy's law!!!
Not sure if I will have the car finished by the end of the month.....about the cars 50th birthday.
Lyle
 
Got my pressure switch from TRF.
Checked the connecting pressure, it was 58-60 PSI.
Put some teflon tape on the 1/8 NPT, removed the old one and screwed in the new one. Did it fast and only lost a few drops of fluid.
Plugged it in and the brake lights work!
Thanks for the help.
Lyle
 
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