Hydraulic brake switch

[el torro]

Thinking of changing electrical switch to hydraulic one on my 73 +2, anyone have thoughts/done it

[p.faurie]

Yes I've done it on my +2, I have a spyder chassis on my car(if it matters) down on the o/s/f horizontal chassis rail there was the 4 way brake pipe connector,I replaced that with an early +2 one with the switch in it,then extended the original brake switch wiring down to the new position,I believe the 4way pipe Union is a generic one,the reason I went with the hydrolic one was that I couldn't change the original one

without removing the pedal box as it snapped off when I tried to adjust it because it wasn't working correctly,I bought a new one, took the pedal box off ,fitted it,adjusted it on the bench so to speak with an ohm meter by pushing the brake pedal a bit to test the circuit,went to refit the box and the switch was fouling the bodywork in front of the pedal box,don't know why, didn't fancy taking it off again so went hydrolic,the mechanical one looked cheaply made in my opinion I think it was a copy not an original,off a mini I think.
Good luck phil

[ericbushby]

Just a thought with hydraulic brake switches.
Whereas the mechanical switch detects movement of the brake pedal, the hydraulic switch responds to a minimum brake fluid pressure.
Occasionally I get helpful drivers telling me my brake lights are not working, but that is because a lightweight car needs very little pressure to bring it to a halt gently, and sometimes not enough to operate the switch.
There is nothing wrong with the switch.
There may be some advantages to the mechanical system.
Eric in Burnley
1967 S3SE DHC

[prezoom]

I can verify Eric's reasoning on the hydraulic switch as used on my S2. On a spirited drive through the local mountains, a friend following me told me my brake lights were not working. A hard push on the pedal at a break in the drive, showed the them working. I have also had a hydraulic switch fail, although it was the original and probably passed its use by date.

[mbell]

Personally I'd stick with the original. As it seems like a lot of work for not much gain.

Only reason I can think that would justify it to me is for two stage brake lights. So you could have the hydraulic switch enable really bright brake lights (or hazzards) when breaking hard.

[john.p.clegg]

Why not Belt and Braces, I have a hydraulic switch ( on my mm ) and it only operates If I stamp on the brakes...not a happy bunny so fitted a micro-switch that operates as soon as the pedal is touched...the two operate in parallel ...gives the morons behind more thinking time...

John

[Foxie]

Why not Belt and Braces, I have a hydraulic switch ( on my mm ) and it only operates If I stamp on the brakes...not a happy bunny so fitted a micro-switch that operates as soon as the pedal is touched...the two operate in parallel ...gives the morons behind more thinking time...

John

That's my thinking too !

I've adjusted the mechanical switch to operate as soon as the pedal is touched. Helps discourage tail-gaters !

[JonB]

My mechanical switch fell apart one day. I popped it back together and I think (must check) the lights are working. This has me thinking - why not fit a switch inside the car that operates on the lower side of the pedal fulcrum? I know a lot of modern cars work like this so the parts cannot be hard to come by. You'd need to mount it appropriately but I think it is doable.