LED idiot-lights and other joys

[Daddy Dom]

I've just had a weekend of minor fettling my 1983 3FD in which I fitted LEDs in my idiot-lights, the ones with the built-in resistor. Wow. I love them but most of all I love the sultry GREEN ones I put in the speedo and tacho. Mmmmm. Less drain, more brightness yet not as intrusive to the eyes on dark stretches.

I have a question with the amber indicator idiot-light though - the LEDs are sensitive to polarity, unlike the bulbs and all the others worked only one way round (I tried them all both ways just because ). The indicator one will only flash with one side OR the other, depending on which way the LED is inserted, so I put the bulb back in for now.
Any clues, anyone? A previous owner fitted Oxford mini-indicators (yuk) but I imagine the wiring (though not the relay thingy) remained the same as standard. I'm hunting for some CEV rectangular ones.

The other thing I did was replace all the blackened, yellowed and petrified breather hoses with new ones. She's looking good under the hood!

Cheers, DD

(BTW, my neighbour has fitted blue "pimp-my-ride" lights under the tank of his Monster. Should I expect to hear it talking to him next? )

[3potjohn]

I removed my mini-indicators and fitted those "Flexi-Stem" indicators obtainable from Vehicle Wiring Products.These have the advantage that a) they are easily obtainable b)they only use a 9v bulb c) they are much lighter than my original Morini indicators.) d) I got extra "thin-wall" colour coded wire whilst at it.e) and a proper crimping tool.
However the threaded diameter is 10mm as against 8mm on the mini indicators, so it necessitated drilling out the holes in the headlamp slightly. I guess I could have drilled new mounting points in the headlamp brackets but didn't fancy weakening the structure.
I only have the rear original Morini pair on my spares shelf as there was a fairing fitted originally, with that rectangular headlamp, also on my shelf.

[hendre]

I'm hunting for some CEV rectangular ones.

I have 2 sets lying around for small money.... will have to post from the Netherlands though

[ringer]

I had the same issue of the idiot light only working on one side. The way I solved it was this:
Wire up the indicators to the idiot light so both LH and RH feeds are attached to the same (+ve) leg/terminal of the idiot light. The other leg is connected to earth. Now this will make both indicators flash simultaneously and very dimly - basically both indicators will be in circuit at the same time whenever you indicate! What you do then is insert a diode into each feed from the indicator between the indicator and the idiot light. What the diode does is allow current to flow one way only through it, so you switch on the LH indicator, the 'juice' flows from the indicator to the idiot light via the diode (because the diode is forward biased) , but is then blocked from continuing to flow to the RH indicator (because the diode in that part of the circuit blocks this direction of flow). And vice-versa. I hope this makes sense. Just make sure you fit the diodes the right way round! I sleeved the legs of the diodes and soldered them directly onto the led, and then soldered the wires from the indicators onto the other leg of the respective diodes. Just be careful you don't apply too much heat to the led whilst doing this. Alternatively, you could cut the feed wire and connect the diode in away from the led (you may be able to use a terminal block to do this, though room is tight in those headlights).
As for sourcing the diodes, I happened to have some lying around ( I have been known to dabble in electronic circuits from time to time) but if you're in the UK, find your local Maplins store and go and ask them what you need - they are usually pretty (geeky) knowledgeable about such things. We are talking cost of pence, not pounds here.

update: I just checked, and I didn't solder directly to the led (diodes would then be exposed to the elements) I did it with a terminal block inside the headlight shell.