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March 14, 2021
(pi day)

Exterior Lighting

I've spent the winter this year working on things that can be done in the warm shop rather than in the chilly garage.  The last week or so was occupied, among a few other things, by the exterior lighting assemblies.  There isn't anything much remarkable about these items.  They are pretty much all Lucas products, and so they do have their challenges as far as reliability and longevity go.  Most of the assemblies were complete without much overt damage.  The headlights must have been in a different box.




Other than a few mods to enhance reliability or ease of installation, the only major change in these parts was to go to LED lamps.  The motivation for this was primarily current draw.  I anticipate adding some significant loads to the electrical system, and I can offset those by reducing the load from lighting. Excluding headlights, with all exterior lights on, I calculate the load to drop form nearly 18 amps to just a little over two amps by going to LEDs.  (I realize that having all exterior lamps on at the same time would not be all that common, but it could happen.)




To jump ahead to a particular assembly:

Front Park/Turn Assembly
Headlights
License Plate Light
Rear Turn Signals
Reverse Lights
Tail/Brake Assembly


Front Park/Turn Lights

The front park/turn signal lighting assembly contains a socket for a standard 1156 type lamp for the turn signals, and a socket for the smaller 1895 type lamp for the parking lights.  Standard wattage for these lamps would be about 27 and 4 watts, respectively.

My units looked pretty grody, but from the outside, didn't appear to be damaged.




Inside, they were a little worse.  The zinc plated steel housings had quite a bit of rust.




The rust is not difficult to remove, but since I thought there was enough of the zinc plating left to save, I chose a chelate type rust remover, which will not attack the zinc or the aluminum reflector.  In this case, it was Evaporust.  It's easy to see the difference between the zinc and the bare steel surfaces.




I considered paint to protect the bare steel, but in the end decided to zinc plate the housings.  My hesitation was with the anodized aluminum reflector.  It didn't seem practical to remove it, and I wasn't sure how it would react to the plating process.  I ended up masking the reflector with some lacquer paint.  It dies quickly and is easy to remove.




I tried the process on one housing, and it ended up looking pretty good compared to the other one.




While fiddling with these housings, I noticed that they had square holes for the mounting screws.  However, the mounting screws I found were just ordinary 10-32 machine screws, though I can't be sure they were original.  I'd seen these square holes on Triumph lighting assemblies before.  My TR6 had them, and used a carriage style bolt with a short square shank that snapped in to the square hole.  It seemed unmistakable what the intent of those holes was here, and whether Triumph opted to just use ordinary fasteners, or whether the original fasteners had been lost, it seemed appropriate to go back to the square shank hardware.  They should make installation a little easier.  Mostly, they snapped in and are self-retained,  One had to be helped with a drop of CA glue.  A side benefit of this is that the assembly can be removed or installed without removing the lenses.




Next up was to clean up and install the contacts and lead wires for the lamps, and push on the cleaned up rubber boots. I find it not unusual to find 50 year old British rubber parts to be in very good shape.




Then install and test the LED lamps.  A word about replacing incandescent lamps with LEDs:  Incandescent lamps provide a broad spectrum white light, and this light can be filtered by colored lenses to allow only the desired color range through.  It's a little trickier with LEDs.  Basic LEDs emit a pretty narrow spectrum of color.  White LEDs are typically made by starting with a blue LED, and adding a phosphor to absorb some of the blue light and re-emit it as light more towards the yellow orange part of the spectrum.  This is engineered such that to the human eye, the combined light looks to be a shade of white, but is not broad spectrum like incandescent light is.  For this reason, white LEDs can give disappointing results when used with colored lenses.  It is possible that the light frequency that would pass through the lens may not even be present in the LED light.  For this reason, we need to pick LEDs with a color that matches the lens color.

These are amber LED lamps.  You can't normally tell the color of an LED until it is on.




Cleaned up the lenses...




...and prepared for final assembly.




Oops!  One of the brand new lens gaskets was too short!




No worries.  This is a piece of 3/16" closed cell neoprene foam.  The material is pretty similar to the store-bought gaskets, but a little finer texture, and maybe a touch firmer.  Paper template was made from the fixture itself.




Home made gasket fits way better than the bought one.




Final assembly.





Headlights


My headlight assemblies were just dirty, with a little corrosion in a few areas.




Blasted the buckets and the lamp carriers, and powder coated them.





Cleaned and inspected the pigtail wires and connections.




Installed new adjusters.  These were the only parts I had to buy for the headlights.




And put everything together.





License Plate Light

The license plate light assembly was all there, but was dirty, with some corrosion damage in a few places.  I noticed it used one of those fake bullet connectors that you just wrap the bare wire around.  I'll fix that during wiring.




The chrome cover had a broken corner.  It looks like someone (probably me) tried to solder it, but it didn't hold.




The internals were pretty crusty.  This is bad for electrical continuity.




Apart it came, and the steel parts got stripped and re-plated.




The electrical contacts got cleaned up and tested for good continuity.




Then the unit was re-assembled.




I had noticed that this assembly lacked an explicit ground connection.  Since I'm not a fan of using the car's body as an electrical return path, I added a bullet socket for a ground wire.  Unsoldered joints like this get a coat of dielectric grease to protect the surfaces from oxidation.




This unit also had those square mounting holes like the front turn signals.  Carriage type bolts snapped right into them. 




Added the gasket, and put her back together.  I fixed the chrome cover by epoxying a wire reinforcement around the corner on the inside.  The repair isn't visible from the outside.




Rear Turn Signals




One of my rear signal lights appeared to be intact.  The other had a broken lens, a missing rubber gasket, and a broken off ground terminal.  Here are the parts for the good one.




I endeavored to fix the missing ground on the other fixture:




I was pretty proud of myself until I realized that the rubber boot would now not fit over the new ground terminal.  So I had to backpedal and order a new socket, which appeared to only come with an amber lens (at least from SpitBits).  There appears to be some confusion about which models and years had red, and which had amber lenses.  So I ordered a red lens, too.

I always fear the worst when I have to order parts like this, but the part I got appeared to be New Old Stock.  I was pretty happy with it.  The red lens, though, was definitely not NOS.




The final assemblies.  The mismatching lenses is a minor irritation, but I'll get over it.





Reverse Lights

The reverse lights didn't need any mods or repairs at all.  Just cleaned them up.




Tail/Stop Lights

The tail/stop light assembly was designed for a standard 1157 dual filament lamp.  These lamps have wattage ratings around 27 and 8 watts for the stop and the tail light filaments respectively.

My fixtures were pretty cruddy inside and out, especially around the electrical bits.




Drilling out a few rivets frees up the anodized aluminum reflector, and the lamp holder assembly.




It was obvious to me that the lamp holder needed some serious attention.  Each circuit (tail and stop) had a copper (likely bronze, actually) socket for a bullet terminal, and a copper spring terminal for contact to the base of the lamp.  They were fastened together with a single rivet.  The parts were a little loose, and there was corrosion all over them.  The ground bullet socket had a single rivet as a fastener between dissimilar metals.  This is not a reliable electrical design.




I thought I could turn this into a proper electrical device with a little TLC.  I removed the contact parts from the lamp holder, and freed up the contacts from their phenolic carrier.




The bulb holder got stripped of the corrosion, and any zinc that might have remained.




I was getting ready to zinc plate the carrier when it occurred to me that for an electrical component, copper plating would be more appropriate.




The copper/bronze parts all got rid of their corrosion, then got treated to a tinning bath, along with the lamp holder.  The tin protects the copper from tarnishing, and also makes soldering way easier.




The ground bullet socket got riveted back in place on the lamp holder with a copper rivet, and then soldered.




The two parts of each lamp contact were also soldered.  Those should have been designed as one piece in the first place.




Then they were riveted to their phenolic carrier board.




With so many hot and grounded metal pieces so close together in this assembly, a little insulator sheet was included in the design.  The original wasn't in very good shape, so this is a copy made from 0.010" nylon sheet--a material pretty close to the original.




Finally, riveted the lamp assembly and the reflector back on to the main frame.




The lenses responded pretty well to a good cleaning and polishing.




Oops, forgot to order the lens gaskets, and the one remaining original was stiff as a board. That's OK, I had some foam left over from the front signal lights.




I did have new body gaskets, though.




Looking pretty OK.  There is some pitting on one of the chrome bodies, but I don't seem to be stressing over it.





Conclusion

So this completes the refurbishing of the external lighting assemblies.  They will go in a box until the installation ceremony.




This was a finicky project in places, but I'm pretty confident that these parts are in original condition, or better.  It was fairly cheap at around $75 for various parts and gaskets, some of which I didn't use.

Comments to Ed at elhollin1@yahoo.com

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