Circular amber indicator lights

LED Lighting

by Charlie Plain-Jones

It all started with the comment “You have GOT to do something about your lights!”

Jim and Rhoda Andrews had been following us, both in our VA Tickfords, up the A34 from the Portsmouth Ferry after the 2013 SVW Weekend in France. It was late, very dark and apparently we were almost invisible with our ‘period lighting’ and Jim rightly thought that this was asking for trouble in today’s traffic.

Our ‘Ticcy’ has the standard arrangement of twin 5/21 watt D shaped red tail/brake lights either end of the number plate. At some time a previous owner had added a pair of 1950’s style 21 watt circular amber indicators (from an A35 or similar….) set into the wings which worked well enough but didn’t help identify the width of the vehicle.

Circular amber indicators

Circular amber indicators

The first thought was to replace all the bulbs with brighter LED equivalents but this is not as simple as it might appear. Firstly the polarity would be wrong and secondly the orientation of the bulb holders in the stop/tail units is wrong for LED lights .(see the ‘LEDs Pros & Cons’ below).

The decision was eventually made (those with an originality frame of mind please look away now…) to replace the circular indicators with period rectangular Lucas light units with non tinted frosted glass lenses. These would allow a combination of Red and Amber LEDs to perform Tail light, Brake light and Indicator functions in a single unit, while being positioned close to the outer edge of the vehicle. The standard number plate D lights to remain unaltered – for the time being.

Lucas light

Lucas light

The Lucas light units found in the ‘bits box’ have the part number 464 and have rather pleasing ‘deco-esc’ ridges running the length of the lens (Lucas part no 572656). They can be seen on various quality cars of the 40s and 50s such as Bristols and Rover P types etc., so it was hoped they would not be out of place. These units and the glass lenses do come up on eBay periodically though often with red lenses which would not be suitable if you want to include the Indicator function too.

LED units in insulated plastic case

LED units in insulated plastic case

The actual LED units chosen were not Bulb Replacements but have an insulated plastic case which is a push fit into a circular hole. They project a 40 deg divergence beam so placed pointing rearwards they are certainly bright. As they have twin insulated leads, polarity is not a problem and were obtained from SVC (see Advertisers). Available in a single ‘wattage’ the decision was made to have a single Red for the sidelight, two Reds for the Brake light and a single Amber for the Indicator.

The first concern was would the relative brightness of this set up give a clear distinction between these three different functions which indeed it did with no problem at all.

As an aside I had tried a particular sample of 5/21 watt led replacement bulbs and was horrified to find almost no difference between the sidelight only and the sidelight plus brake light brightness! Effectively, at night, you would have no Brake Lights! So do check this – most important!

LED unit with sealed cable gland

LED unit with sealed cable gland

Looking at the pictures it can be seen that the original twin filament socket was crimped into the housing and was easily removed without damage. This was replaced with a sealed cable gland from Screwfix through which a length of trailer multicore cable was threaded. Trailer cable is very useful stuff as it has all the colour coded cores for the rear light functions of brake, tail and L and R indicators and earth.

A small section of U form aluminium extrusion provided the mounting holes for the LED units and the wires were cut to length, soldered and heat sleeved to the appropriate trailer cores. Fortunately the extrusion was a firm push fit inside the housing and required no additional fixing. As the units would be exposed to all the road filth thrown up inside the wheel arch by the rear wheels, additional protection in the form of a plastic cover fastened over the gland was thought to be a good idea.

Taking courage, the existing circular holes in the wings were extended into rectangles which ran parallel with the ridges in VA rear wings (and not with the wing outer edge which is subtly tapered as we found out). The appearance of these lights, now installed, is very pleasing and in keeping with the VA appearance – we think. Hopefully you will agree?

But the job is not over yet.

The brake and side lights can easily be wired in parallel with the existing rear lights and a dedicated Earth return is definitely a good idea for all our cars, whether LED or filament bulbs are used.

Special arrangements need to be made for the retrofitted Indicators however. Standard flasher units are current driven and work on a heated bi-metal strip principle. The amber LEDs draw a fraction of the current of their 21 watt filament equivalent and so a replacement solid state flasher that is not current dependant is required. These units will flash up to 15 amps of load so it is quite possible to mix filament and LEDs in the same circuit without overloading them.

Next it is round to the front of the car to replace the indicator bulbs there too.

In our car the said owner had grafted a white 5 watt plus an amber 21 watt bulb into the standard sidelight, which looks a reasonably neat arrangement except for one thing – Heat. 21+5 watts in such a confined space can lead to cracking of the glass lens – I know this for a fact. So an amber white LED pair installed here solves both the heat and the flasher loading issues – ‘simples’.

Hopefully next time Jim and Rhoda are chasing us home from an SVW weekend they will need sunglasses, even at night…

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