T-Series Looking for brake light switch to last >6 months??

[RickB]

I love the little switch I got from NicCJ on ebay - very easy to install - but... the first one lasted about 6 months then failed.
I emailed him, he had never heard of this happening and showing a great deal of class and customer service he sent me a new one for free. The thing came in a green box that said LUCAS on it.
It just went out after about 6 months.
This just aint right.

Ok, just noticed I am posting in MG but the switch for the 78 Midget & the MGB is the same so please just point the way to a switch I can get that will last me some number of years. The original switches lasted decades, so that's not too much to ask right?

Thanks!

 

[Steve_S]

Re: Looking for brake light switch to last >6 mont

The current replacements are garbage, and they fail all the time. If he's never heard of this problem then he probably doesn't sell very many!

Half way down this page: https://www.mgnuts.com/products/

<div class="ubbcode-block"><div class="ubbcode-header">Quote:]Catagory: Brakes
Product Name: Hydraulic Brake Switch (low pressure)
Vehicle Application: MGB
Manufacturer # SW-32
Description: The latest crop of replacement brake switches for early MGB do not last long and cannot withstand the use of silicon brake fluid. The SW-32 switch from Ron Francis Wiring is a high-quality unit and a direct replacement for the original. It is the same overall size, but does have a different look from original. The body is silver and round, and the connector is a modern plastic one with high quality terminals. Until someone produces a quality OEM-style replacement, this is all I will use.[/QUOTE]

 

[Shinsen774]

Re: Looking for brake light switch to last >6 mont

Putting a relay on the switch seemed to help (mine is '64). You can set it up yourself or get one from a guy named Dave DuBois (found him on mgexperience.net) for just a few bucks. That's what I did. The switch has lasted....so far. My last one died quickly. When I put the new one on, I added the relay as well. I use DOT5 fluid, but I think the silicon may be unfairly getting the blame based on what I have read and heard.

 

[RickB]

Re: Looking for brake light switch to last >6 mont

I really don't see how the fluid would come into play at all.

I've only ever had 69 & later cars but none of these were designed to have fluid contact the brake light switch. The pedal linkage fulcrums against the switch, when the pedal is pressed the actuator leaves contact. No fluid is involved (hypothetically - of course there's always spillage / leakage to consider)

 

[David_DuBois]

Re: Looking for brake light switch to last >6 mont

"I use DOT5 fluid, but I think the silicon may be unfairly getting the blame based on what I have read and heard."

The above is very true statement. I have had silicone fluid in our TD since I finished restoring it and it ran for 25 years before the original switch died of old age (I have no idea how long the switch had been in the car before we got it - for all I know it may well have been the original switch). I stuck two or three replacement switches in the car and none lasted even 6 months (Rick - you got good millage out of your switch). That is when I went to work experimenting with relays and arc suppression circuits. That was ten years or more and I have not had a single failure since - even with silicone fluid in the system. I had the same problem with our 66 MGB (also with silicone fluid) and I switched to the pedal operated switch thinking that maybe there was some credence to the claims about silicone fluid - that switch (a replacement rather than OEM switch) didn't even last 2 weeks! and it is nowhere near the brake fluid!!

Rick - there are two ways to cure the problem you are having. You can make up or purchase a relay/arc suppression circuit in accordance with the instructions on my web site at: https://homepages.donobi.net/sufuelpumps/ Brake Light Relay under the Other Tech Articles section. The second option is the SW 32 heavy duty brake light switch that Steve S is running in his car. These switched are available from Ron Francis Wiring at: https://www.ronfrancis.com/showpage.php?page=main.htm
Cheers,

 

[RickB]

Re: Looking for brake light switch to last >6 mont

Thanks Dave,
the SW 32 looks interesting, but I don't understand why there are two parts? And what are those connectors on the back?


When I found I needed a switch the first place I went was the boxes -o- stuff given to me by the PO of my current MGB.

Something I have learned from these boxes is even though it says "Oil Filter" on the box don't believe it - look inside. One such box was full of front bushings! Breand new!

I got all the way to the bottom this time and at the bottom was a box that said something like: "suspension kit".

Inside... a brand new front suspension kit for the MGB!! WOOHOO JACKPOT!!!

I was very happy!

 

[Steve_S]

Re: Looking for brake light switch to last >6 mont

The silver part is the switch. The black part is the connector.

 

[David_DuBois]

Re: Looking for brake light switch to last >6 mont

Rick - I guess that we should have asked which brake light switch you have on your Midget. Since you show in your signature block that you have a 78 Midget, I am guessing that you have the pedal operated switch rather than the hydraulic switch. If this is true, then the SW 32 won't work for you as it is a hydraulic switch. Also, going back to your first post, the green box Lucas items are replacement items rather than the really good NOS red box items.

Now a question for you that will help me in a project that I am working on. Is the location of the fuel pump in your MGC the same as on the early MGBs, ie. in a bracket just in front of the right side rear wheel? I am putting together an article on the proper mounting location of the OE (SU) fuel pumps on all of the post war MGs and the MGC is one that I forgot to ask about.
Cheers,

 

[RickB]

Re: Looking for brake light switch to last >6 mont

Hi Dave, yes it's the 78 so yes it is the one that is pedal operated.
Any ideas on a good replacement for it? - wish I could find a good NOS switch.

To the best of my memory that's right about the fuel pump, I will see if I can get out there today and confirm.

 

[DrEntropy]

Re: Looking for brake light switch to last >6 mont

Wow, Rick! Congrats on th' spares find. I've had that stuff takin' up space in th' Shed for years now, just about time to renew all on Her B. Gotta go with poly bushes, too.

IIRC, I've replaced those switches with a "MicroSwitch" wired as N/C in past. And hung a relay in th' circuit.

 

[RickB]

Re: Looking for brake light switch to last >6 mont

I guess its just strange that the originals lasted decades. It makes you expect too much from a replacement I guess.

 

[jlaird]

Re: Looking for brake light switch to last >6 mont

Nothing wrong with old time Lucas. So much of it is still working 40 years later.

 

[David_DuBois]

Re: Looking for brake light switch to last >6 mont

Hi Dave, yes it's the 78 so yes it is the one that is pedal operated.
Any ideas on a good replacement for it? - wish I could find a good NOS switch.

To the best of my memory that's right about the fuel pump, I will see if I can get out there today and confirm.

Unless you can find one of the red box Lucas switches, or jury rig a quality micro switch as Dr. Entropy suggests, I don't know of any other switches. The easiest way I have found is the addition of the relay/arc suppression circuit to one of the green box Lucas switches (that is the set up I have on our MGB).

thank you for the confirmation on the fuel pump for the MGC.
Cheers,

 

[RickB]

Re: Looking for brake light switch to last >6 mont

I dug up a spare relay out of my 'big box -o- stuff' and found it to be good for this application.

12 VDC 30A ought to do it eh? Nice inline fuse too!

So I tested it & found it good (brand new but I still like to test first).
Hooked it up to my switch and wired the contacts to the brake light wiring and:

WaHoo - I have brake lights!!

Thanks everyone, another job behind me (for now).

Dave, My big blue book: BMC Service Parts List for MGC - also confirms that location for both the MGC Roadster and GT.

 

[David_DuBois]

Re: Looking for brake light switch to last >6 mont

Rick - "My big blue book: BMC Service Parts List for MGC - also confirms that location for both the MGC Roadster and GT."

Thank you, I will now include the MGC fuel pump location in my article.
Cheers,