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Brake Pressure Switch Thread
mikeb - 29/9/14 at 12:34 PM

Its been a while since I looked at this but just wanted to check before I do a first bleed of my brakes.

I purchased a brake pressure switch to go into a standard T-Piece, should this screw down all the way (as per the standard fittings) or are the threads designed to bind after about 6 turns to seal? (seem to remember the switch doesn't have the taper on the end like this one
C16062A BRAKE LIGHT SWITCH (HYDRAULIC) FOR CLASSIC MINI

so confused how it seals in a T Peice.

M


loggyboy - 29/9/14 at 12:39 PM

I bought a mini one and it was the wrong thread pitch (that exact type from that exact shop in fact). Spoke to RAW and they sent me the correct one, but no idea what thread it should be.

[Edited on 29-9-14 by loggyboy]


adithorp - 29/9/14 at 12:57 PM

It depends how classic they mean by "Classic Mini".

There are 2 thread sizes, M10x1 and 7/16unf. The switches for both sizes are taper thread. and will tighten up as you screw them in. Both were used on Minis.

Unfortunatly m10x1 and 7/16unf are very close in size, difficult to tell apart and will bind up if screwed in (like a taper thread does) to each other.


mikeb - 29/9/14 at 12:57 PM

I couldn't' find the ebay listing but pretty sure mine was a lucas mini one. its been ages since I bought the t piece that I can't recall what thread it is.
Should it do up all the way down?


mikeb - 29/9/14 at 12:59 PM

When I ordered I remember checking that I got the right thread (think m10) and still have the box.
If its on a tapered thread its should be ok then just to tighten up, its seems to screw down more turns than I would have expected if it was a mismatch thread

[Edited on 29/9/14 by mikeb]


CosKev3 - 29/9/14 at 02:31 PM

No it shouldn't screw all the way down,be careful as you can split the brass T piece screwing them in too far

I use some thread lock/seal on them.


adithorp - 29/9/14 at 02:49 PM

M10 presure switch is pt no 51650 in Intermotor. Sorry not got any cross ref to check other makes. It is a taper thread and will tighten before it bottoms out.

M10 switch won't start in a UNF fitting (just tried my spare) but a UNF male nut will screw into a m10 fitting but it's very lose fit so you should know it's wrong.