extra stop/brake light

[twas_brillig]

One other thought: for magnets, have a look at Lee Valley Tool:
https://www.leevalley.com/en/garden/page.aspx?p=75447&cat=2,42194,72101 for a flexible (but not theft-proof) unobtrusive mount for GPS/whatnot
https://www.leevalley.com/en/Hardware/page.aspx?p=32065&cat=3,42348&ap=1 choices in diameter and strength for mounting that third brake light
https://www.leevalley.com/en/wood/page.aspx?p=44536&cat=1,42363,44536 not sure where to use it on a car, but it's a great stocking stuffer
Me, I like magnets. I'm sure that equivalents are available from many sources, but at least this site allows a comparison of sizes/strengths. And I'll be doing a bit of thinking come spring about attaching an LED bar the outside of our BJ7 tonneau and convertible top using magnets on one side of the fabric and a steel backing piece on t'other. Doug

 

[AHBN1]

Hi Doug,
The brake light I've used was available on various GM SUVs from 1992-2000 (and I think on 2002 Hummer). I opted to use magnets and clips to hold the light in place instead of attaching to the tonneau as I don't always drive with the tonneau. If I remove the tonneau or get caught in the rain and have to put up the top then I'd have to remove or re-position the brake light. Putting the top up in the rain takes long enough, don't need to re-set the light to and add to the wet. I hope that's helpful to those reading this thread.
I do have a question for some readers. Why add a new switch or run wiring through the car from the brake switch when the wiring is right there in the trunk/boot and can be easily accessed and hidden? Just seams like one more thing that can go wrong and the existing system is adequate. If I'm missing something I'd like to know so I can change it if needed.
Thanks,
Dave

 

[twas_brillig]

Thanks Dave - hi ho, hi ho, off to Pic'n Pull I go!
Randy: where did you source your four way block replacement for the three way? Are there compatibility issues between North American and British brake flares?
All: have a look at this thread from July 2016 regards third brake lights: https://www.britishcarforum.com/bcf...hird-brake-light-ideas&highlight=randy+forbes (Randy: you get star billing as I did a search for you name, with the date of your brake block photo) as well. Doug

 

[steveg]

Federal Hill Trading is a great resource for brake line info and fittings etc.
https://store.fedhillusa.com/

 

[CraigC]

Hi Doug,

I do have a question for some readers. Why add a new switch or run wiring through the car from the brake switch when the wiring is right there in the trunk/boot and can be easily accessed and hidden? Just seams like one more thing that can go wrong and the existing system is adequate. If I'm missing something I'd like to know so I can change it if needed.
Thanks,
Dave

The answer is fairly simple. The wire you refer to in the trunk is not a "stop light" wire. It is a dual purpose wire that operates the stop and turn light and there is one for each side of the car. Those two function share a common filament in the bulb. Which function the wire performs at any given time is dictated by the relay box on the left inner fender. When you apply the brakes while a turn signal is operating, it allows the turn signal function to override the brake light on that side. Now, imagine how your high mounted 3rd brake light would work if you tapped into one of those two wires, or worse, if you tried to tap into both. The simple solution really is a wire run from the front, either from the stop light switch or the stop light switch input at the flasher box.

Your idea would work on a car with a separate brake and turn signal light. I believe the late BJ8 would fit that description.

 

[AHBN1]

Hi Craig,
Thank you for the response. Although I understand what you're saying I must be missing something. My cars are a BN1 and BN6, both of which have the third brake light wired as described. The third brake light has had the light bar split into two allowing for the turn signal circuit to function on the right and left side of the light bar as needed. Each of the cars has a combined brake/signal/parking light bulb (#1157 I believe) with no separate light as per the BJ8 and everything works as it should with no issues. All I've done is run the wires from the light to the brake and signal circuits via original bullet connectors and it's been working great on both cars for the past 10 years or so. I'm just a hobbyist, not a mechanic so my philosophy is "if it ain't broke don't fix it" but now I'm curious. Any further comments would be welcome.
Thanks again,
Dave

 

[Randy Forbes]

Hi Craig,
Thank you for the response. Although I understand what you're saying I must be missing something. My cars are a BN1 and BN6, both of which have the third brake light wired as described. The third brake light has had the light bar split into two allowing for the turn signal circuit to function on the right and left side of the light bar as needed. Each of the cars has a combined brake/signal/parking light bulb (#1157 I believe) with no separate light as per the BJ8 and everything works as it should with no issues. All I've done is run the wires from the light to the brake and signal circuits via original bullet connectors and it's been working great on both cars for the past 10 years or so. I'm just a hobbyist, not a mechanic so my philosophy is "if it ain't broke don't fix it" but now I'm curious. Any further comments would be welcome.
Thanks again,
Dave

Key sentence; if someone is using a single-circuit 3rd brake light (which is exactly what I'm using) then Craig's explanation is spot on. You're getting away with it, because your left and right side taillights are still isolated from each other.

The same could probably be accomplished with a single-circuit 3rd brake light and the correct placement of diodes, but the redundant pressure switch at the rear brake pipe junction was lot easier for me to comprehend.

I'm pretty sure I got all the parts I needed__4-way block & pressure switch__from Holden, so no incompatibility issues.

https://www.holden.co.uk/displaypro...06&agName=Brake+Pipe+&+Fittings&pCode=065.649

https://www.holden.co.uk/displaypro...35&agName=Brake+Light+Switches&pCode=54033360

 

[CraigC]

Dave, you may want to check your state's vehicle code. I believe states typically do not allow the center high mounted light to have any function other than a brake light. Flashing lights of any kind would be prohibited. Exception to this rule would include emergency vehicles.

 

[AHBN1]

Thanks Randy. I now see where the confusion is/was for me. Craig, I'm in Ontario, Canada and I've checked our regulations which in part state that no red flashing lights are allowed facing any direction (emergency vehicles exempted) unless used as 4-way flashers or tapping on the brakes to produce an on-off effect. Oddly the law doesn't suggest turn signals with red lighting would be allowed and yet cars are still built this way. Given how small the tail lights are on our Healeys I'd rather have the flashing light than be rear ended by someone trying to read the name badge on the trunk lid of the car. I'll take the ticket if the law doesn't like the enhanced visibility.
Thanks again Guys,
Dave

 

[steveg]

Key sentence; if someone is using a single-circuit 3rd brake light (which is exactly what I'm using) then Craig's explanation is spot on. You're getting away with it, because your left and right side taillights are still isolated from each other.

The same could probably be accomplished with a single-circuit 3rd brake light and the correct placement of diodes, but the redundant pressure switch at the rear brake pipe junction was lot easier for me to comprehend.

I'm pretty sure I got all the parts I needed__4-way block & pressure switch__from Holden, so no incompatibility issues.

https://www.holden.co.uk/displaypro...06&agName=Brake+Pipe+&+Fittings&pCode=065.649

https://www.holden.co.uk/displaypro...35&agName=Brake+Light+Switches&pCode=54033360

The Holden 4-way adaptor doesn't specify whether it's SAE or DIN(Bubble) flare. FedHill sells the latter. If bubble you'll need to add bubble-to-sae adapters for the two axle brake pipes.

 

[Gliderman8]

Here's a third brake light I built for my TR6. It's not magnetic, but it does not damage the paint as it just slips into two slots under the trunk. It's very easy to put on and take off.
https://www.britishcarforum.com/bcf...Winter-Project-complete&highlight=brake+light

 

[Randy Forbes]

The Holden 4-way adaptor doesn't specify whether it's SAE or DIN(Bubble) flare. FedHill sells the latter. If bubble you'll need to add bubble-to-sae adapters for the two axle brake pipes...

The Holden piece's internal configuration matched the one I removed, and there were no leaks then or now, so I'm good.

At some point, there's one (1) more upgrade I'd like to make to the brake system, and that's to fit a dual circuit m/c. Problem is__besides the time to devote to it__is that I had already made the pedal box as narrow as possible, so I could put an air filter on the 3rd/rearmost Weber carb.

 

[steveg]

I made an adaptor from 2 x 2 x 1/4 aluminum which allowed me to mount a 3/4" Fiat 124/131 dual master cylinder in the standard position.
See:
https://www.pbase.com/stevegerow/image/157683927

 

[twas_brillig]

I assume that the 3000 and the Sprites all used 3/16" brake lines, which means that the 5 connection brass front splitter for our BE could also be used to replace the 3 connection splitter on the 3000 differential - AH Spares refers to the Sprite part as XBRK229; the 3000 as BRK259; both have bolt holes but somewhat different configurations. A shop I go to suggested looking at Triumph - Moss Motors part 589-120 is another option. I'm sure that there's more choices (Moss Motors 180-230 for MGB/MGA, etc.). Doug