Technical brake light switch

[gordinir8]

Anyone knows what thread size is the brake light switch? Can i use any switch i will find available localy or it has to be a 500 one? Maybe it is common with a modern fiat?
If i remove it all the hydraulic fluid will come out of the system?
Thomas

 

[the hobbler]

Hi Thomas----yes, the brake fluid WILL all come out when you remove the switch. I would advise you to put a clamp on the pipe from the reservoir down to the master-cylinder (it is a flexible pipe). You will also need to re-bleed the brakes--start at the wheel farthest from the master-cylinder and finish at the wheel nearest the master-cylinder.
I managed to find a picture which showed the threads of all the orifices of the master-cylinder---it had 1/8 for the switch, and ref. previous thread, we came to the conclusion that it was possibly 1/8BSF--a 'pipe' size. I would definitely recommend that you fit the correct Fiat switch--it is matched to the master-cylinder and the system.

 

[gordinir8]

Thanks for the info, i will go for an original one as advised, hate to bleed the system again. Previous owner had installed a mechanical switch above the brake pedal with a spring etc. I discard it and connect the original switch which worked for sometime.

 

[AndrewHarvey]

The switch above the pedal is a 126 pedal box.....