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MG Midget and Sprite Technical - New brake light switch

I need to replace my brake light switch (hydraulic type), the question is where can I get a decent one ? Has anybody bought one recently that appears to be decent quality ?

I seem to remember that a couple of years ago there was an article on these , somebody was cutting them in half to investigate the quality, I cant remember the conclusions. Was the article in MASCOT ?
Ian
Ian Webb 1973 GAN5

I've had a few recently. The usual one from the supplier that rhymes with toss lasted a few weeks. I decided to get a good quality OEM one off eBay made by Bosch and was so branded. Paid 15 plus postage IIRC. Lasted about 100 miles and it was probably the emergency stop I had to perform driving to the Portsmouth ferry for a 1 week holiday in France.
After that I went on another tack. I bought the mechanical one usually fitted to the midget 1500. At the front of my pedal box inside the engine bay I found 2 holes which were originally intended for brake and clutch pedal adjusters that my car (Frog) never had. I enlarged the hole in line with the brake pedal to fit the mechanical switch along with a washer or two to get it the right distance from the clevis pin. This was more successful. It lasted 4 or 5 days into our next French trip. A fellow traveler informed me it was now flickering. At the next hotel I had a look, took it off but couldn't figure out why it flickered so put it back on and it had stopped altogether. Eventually I noticed movement on the switch where the crimp that retained the two halves of the switch together appeared to be loose. Took it off again and using pliers made the crimp more secure, put it back on and ever since it has worked OK.
Parts today seem to be crap no matter what you pay.
Saying that, I have heard that Harley Davidson sell a hydraulic pressure switch that has the correct thread but haven't pursued it any further.
Rob
MG Moneypit

OEM Lucas ones (not green box) pop up on Fleabay quite regularly.
Bob Beaumont

I had several fail in quick succession, until I added a relay since when it's been ok. I guess changing stop lights for led bulbs would have the same effect of reducing the current through the switch, though I am not saying this is the only problem.
GuyW

I have a few second-hand OEM switches that I've been saving, just in case.

I also fitted a relay to my brake light switch recently. The switch has been on my car ever since I bought it (1986) and may well be original. Hopefully the relay will extend its life even further.


Dave O'Neill 2

Relay is a sensible approach.
I changed mine for one for a Mini bought on ebay about 10 years ago and it cost then about £1.50. It's still going strong.

https://www.ebay.co.uk/itm/CLASSIC-MINI-BRAKE-LIGHT-SWITCH-PEDAL-1976-13H3735-ROVER-FLOOR-AUSTIN-BMC-6J6/391824750187?hash=item5b3a93366b:g:9R8AAOSwnK9ZTl89

Others have derided such cheap tat (now £2.75 incl p&p) but I believe setting it up properly with washers as spacers to allow the plunger to not exceed its designed travel has contributed to extending its life expectancy.
As Rob mentioned, it fits in one of the pre-dilled holes in the pedal box assembly.
It's supplemented with a relay and a diode (to stop interference with the ICE :] LOL)





Jeremy MkIII

Ian,
a reliable source of reliable Lucas brake light switch has been L M S Lichfield - their website shows as they only have one left now (hence the higher price of £10 no doubt) so you better be quick if you want it - otherwise I have a spare that works as I tried out the one from Lichfield and left it on the car, would swap for slave cylinder and I give you money, meet at Pitsford. :)

"SMB423 brake light switch- Lucas - Product no.: Lms0346"

"Brake light switch, SMB423 alternative numbers 39721, JCB 701-03100, 1/8" x 27 NPTF, with lucar conections These switches are from our old stock packed before 1999 some are in old green boxes some are without their box Ex military vehicle parts surplus stock we have 4 only SMB496 with the same nato number!, Ex military vehicle parts surplus stock LAST ONE"

http://www.lmslichfieldltd.com/
Nigel Atkins

Harley-D. About £27.


Alan Anstead

I eventually remembered where I saw the brake light switches cut up to reveal their innards, its on the MGAGuru website , worth taking a look at.

Nigel, I already knew about LMS Lichfield, in fact they don´t have´any stock of the NOS SMB423 switches.

I did manage to work out the Harley Davison 1/8¨ NPTF switch , as fitted on the rear brakes of Harleys in 1970 & 80s , but thanks to Alan for confirming the part number.

Also I have found that Bosch still supply new suitable 1/8¨ NPTF brake light switches, fitted to many older German cars and agriculteral machinery.

So in conclusion I will be trying either the Bosch or the Harley switch. The Bosch is much cheaper than the Harley so that will be the first try .
Ian
Ian Webb 1973 GAN5

Ian,
my memory isn't the best so check the (MGB?) Archives as IIRC someone bought a Bosch and it didn't last - but as you know don't rely on my memory.

If you're stuck I do have still the switch that was previously fitted and worked fine just couldn't be bothered to swap back so left Lichfield switch in - even protected the spades on it for storage.

Sorry about Lichfield site and stock - so many companies enormous, big and small have their websites so out of date and full of errors and many seem to leave them that way even when notified/told/mentioned.
Nigel Atkins

"IIRC someone bought a Bosch and it didn't last - but as you know don't rely on my memory"

You don't need the archive - it was posted at 15:01 this afternoon, by Rob. Post no. 2 ^^^^^^
Dave O'Neill 2

OK Dave O - I'll bite, what's that u/j in the steering column for?
David Smith

David

MGB
Dave O'Neill 2

I have the mechanical brake switch on my 1500. The standard part is garbage, and its a pain to fit because you have to lift the pedal box slightly to screw it in / out.

There is an Intermotor one that is a direct replacement and screws in without lifting the pedal box. Its also better made.

With the Intermotor switch and led brake light bulbs its seems to be holding up so far....
Chris Madge

Alan
Do you have any experience of how long the Harley D switches are lasting ?
Ian
Ian Webb 1973 GAN5

Ian
Longevity has to be the question. One of my Masc area members (i am Area Rep) has had pne fitted but a few months and the other, whose photo I put up, only fitted his this week.
Alan


Alan Anstead

I've ordered a Harley switch as shown below by Alan, it was £22.39 on Fleabay, so I thought as it cost only slightly more that the Bosch ones it was a better option.

Ian
Ian Webb 1973 GAN5

This thread was discussed between 28/11/2019 and 02/12/2019

MG Midget and Sprite Technical index

This thread is from the archive. The Live MG Midget and Sprite Technical BBS is active now.