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Please help! turn signals.

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N

nomad

Yoda
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Well I'm tearing what little hair I have left out trying to figure out a turn signal problem.
Turn signals work on a 65 sprite but flash quickly. Indicator bulbs on the dash give one feeble flash when first turned on then nothing.
These are Canadian front signals with 2 bulbs if that could make a difference.
All wiring appears to be correct.
Where do I look!!!??


Thanks in advance,
Kurt.
 
both front and rear work? How are the ground wires? On old American junk, that usually is a sign of high resistance. I don't know what flasher a '65 uses, so I can't comment any further.
 
Sounds like not enough resistance in the circuit to me. Have you checked that ALL the lamps flash? Generally the "quick flash" is how you tell it's time to replace one. Same thing is indicated by the one flash of the dash bulb, after that first current surge there's not enough time to heat its filament. ..

Just a guess.

If you pick up a new flasher unit from, say NAPA, you can then use the new LED light units that don't work with our old bimetalic style units.
 
Thanks folks. All bulbs appear to flash nice and bright and even. I'm afraid I have to substitute the flasher first, try that tommorrow night. Hate the idea of losing my original lucas stamped flasher!

Bill, can you elaborate on LED units that I assume can be substituted for the bulbs we use now?

Thanks, Kurt.
 
they fit the same sockets, but they don't draw the current needed to operate a lucas flasher unit.......

Lucas units operate using a bimetalic strip, the kind of set up used in old style mercury switch thermostats. .. as current flows the strip heats up, and since it is of two metals, they sides expand at different rates causing the stip to curl. When all the bulbs are working properly the current draw is enough to bend the metal enough to break the contact, current stops, the strip cools, connects and the process starts all over again. If one bulb is out, not enough current is drawn to heat the metal enough to break the cicuit, so they lights stay on, OR, it just barely breaks and you get rapid flashing. LED units draw next to no current, so they just stay on, UNLESS you replace the flasher unit with a modern electronic one. Bill M. did this while we were on the road a couple of years ago, but doesn't yet, to my knowledge use the LED replacements.

A guy at the ABFM had a whole tail light assembly with multiple LEDs for SUPERBRIGHT tail lamps, and suggested adding in a resistor if one wanted to use and original Lucas flasher.
 
Thanks Bill, I priced LED repacement bulbs at my local parts store. He quoted $40 to $70 apiece!! When I can buy a LED keychain flashlight for a couple of bucks I'm thinking there has to be another source or will be shortly.

Substituting a Wagner flasher unit gives me an occasional flash of the indicator lights but not a solution to my problem. Any more suggestions????

Tnx, Kurt.
 
Mark Doust (abarth69) might have some LED flasher bulbs that are a straight swap.
 
Regarding LEDs, when I replaced the lamps on my Bugeye dash I got them here: www.superbrightleds.com. A word to the wise--now the turn signal indicator is positively blinding. At night it is too bright for my taste.

I have not replaced my actual turn signal lamps. I've read about putting the resistor in-line with the turn signal lamps so that the Lucas flasher still works, however...it would seem that this would have the effect of dimming the lamp and would also increase the current carried by the wire. That would kind of defeat two of the reasons you would want to use them--the third being increased lamp life.

On the other hand, I don't know how much actual resistance you have to add to make the flashers work, so I don't know if what adding a resistor would make much difference.

Superbrightleds also sells the flashers one would need to avoid having to install resistors in the circuit.
 
If they're still flashing too quickly with the new flasher unit, ... gosh I've reached the limits of my knowledge. Bill M. can probably figure it out in a couple of minutes. Can you wait until June?
 
The_architect said:
I have not replaced my actual turn signal lamps. I've read about putting the resistor in-line with the turn signal lamps so that the Lucas flasher still works, however...it would seem that this would have the effect of dimming the lamp and would also increase the current carried by the wire. That would kind of defeat two of the reasons you would want to use them--the third being increased lamp life.
Click to expand...

Yes, that's why you would add the resistors in parallel with the LEDs, not in series with them. The turn-signal lamps are 2.1 amps each, so you'd need a 6 ohm, 25-watt resistor for each bulb. These are expensive and, as you say, simply make no sense.

You can, however, get an electronic flasher that will work with any load current. Some look just like a standard thermal flasher. That makes much more sense, to me.
 
I hoped you might weigh in Steve. I greatly admire your work.

Thanks for the clarification regarding parallel vs series for the resistor. I wasn't thinking.

I had also thought that one could use a simple LED flasher circuit to drive a 12V relay capable of carrying the current--although that is probably only the sort of thing a circuit-nerd would spend time fabricating, as opposed to simply buying a flasher.

The circuit at the link which uses the LM555 timer chip is excellent and easy. Hard to believe, but most of the parts for any of the circuits I have referenced can still be found at Radio Shack.

Charlie
A circuit nerd and proud of it
 
Wow, obviously some real electrical talent on this list! I appreciate the info. Wondering if the electronic flasher will make my dash indicator lights work since that is the only real headache I'm having.
And Bill, I may have to wait that long.

Tnx, Kurt.
 
As for loosing the original Lucas flasher, just buy any 3 prong flasher unit at any auto parts store, unroll the lower lip of the aluminum housing, do the same with the original Lucas, now just swap out the guts, put the new guts in the Lucas housing and it now looks original.
This sure beats the junk Lucas flashers made in India. And for alot less $$
 
If its just your dash lights, do what the rest of us do. Drive for miles with the blinkers on.
 
Thanks for all the insight!! Sorry I have'nt got back till now. I suspect a high resistance ground somewhere just because I've had problems with them in the past. Bill L is quite logical and Spritenut has a great idea. The architech with superbright led's has a sight that I think I'll use. Only problem with an electronic flasher that I can see is that I have a positive ground car with a working early tach so will probably have to be careful when wiring it. Assuming that it is polarity sensitive.

Thanks again,

Kurt.
 
Ah, now...that positive ground thing may be a snag, Nomad. LEDs "generally" are negative ground only. That said, at some point I did locate some positive ground LEDs for vintage cars, but I decided in the end to convert to negative ground for a number of reasons, most of which are familiar to everyone. This commentary on positive ground LEDs and flashers is worth reading.

If you do get this positive/negative bug worked out, let me say that the only part of my turn signal system that uses an LED is the indicator lamp on the dash. The turn signal lamps are stock incandescents at this time. Therefore, I'm able to continue using a standard flasher.

One of the reasons I converted to negative ground is that eventually I probably will install LEDs elsewhere--that is, once the prices come down, which they surely will.

Charlie
 
I was thinking about the flasher unit and if you are careful as to polarity and don't let it ground to the body I should be fine. Forgot about using the bulbs, they won't work unless you get ones specifically for positive ground. It would be easier to convert the tach and go to neg ground. May have to ruminate on this awhile.

Kurt.
 
OK,I can't leave this alone!!Further query. My Canadian front turn signal's have 2 bulbs instead of the one bulb with dual filiments that US signals have. When I turn on the signals both bulbs are lighting even though one is for running lights. I suspect a poor ground somewhere but where? How is this feeding back thru the running light? Would this account for my flash indicator trouble?
Any help appreciated.


Kurt.
 
if you have both bulbs lighting up is really does sound like a bad earth, and the indicator bulb is earthing (or trying to) get an earth through the side light circuit.
Before you buy anything, remove front light fittings & check for rusty connections, clean with emery paper, re-connect & add some grease or Vaseline to help prevent further corrosion.
 
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