VCCA Home Forums TECHNICAL - GENERAL Electrical - 6 volt Timing Light doesn't work on 6v

I've been chasing a timing light problem on my '36. Normally I place a separate 12v battery on the ground and connect to that (instead of using the car's 6 volt battery), and then clamp the transducer to the number one wire. But lately, I can't seem to get a decent light from BOTH of my good timing lights.

My 12v battery is good.
My engine is running, but "surging" some.
I tried a different coil.
Replaced the condenser.
The light might blink once or twice a minute.
I switched to the number two plug wire and got the same result - no or very few flashes.

Any ideas of what else I might try?

--Bill

If you have another vehicle, with a distributor, try both timing lights on It to see If you get the same result. I have had trouble with mine, since It has an inductive pickup that Is temperamental.
Richard

I bought an el-cheapo 12 volt light from wally world a few years ago and it works fine on 6 volts. It's a tad dimmer but still works fine.

Do you have solid wire. The newer carbon type wires do not work very good on these old cars.

My wires are Hyplaon. They seem to be in really good condition.

This week I have tried a separate 12volt battery connected just to the light, a 12 volt "jumper battery", and finally a separate 6 volt Optima. None worked with with lights.

Tonight I borrowed an older Dixson Model 418 and it worked great!!

In researching online, some folks say that the separate battery ALSO NEEDS TO BE GROUNDED TO THE CAR'S FRAME. That's an interesting thought. I might try it tomorrow.

I have done the same thing on my car with a separate 12 volt battery and a timing light. Never grounded the 12 volt battery to the frame and my timing light worked just fine.

I'd check the timing light to see if it works on a 12 volt vehicle. The lamp in the timing light is powered by the battery. The pulse in the plug wire activates the switching circuit to turn on the light. Is is possible that there are lights that require a common ground for the switching circuit? Might be! Some of these new fangled electronic gadgets are built way different.

Most timing lights I have had apart have a ferrite loop that encircles (some of the early models had a sensor coil that fitted between the plug and lead but operated by the same method) the plug lead with several turns of wire that operate the trigger inside the light without a connection to the vehicle (prevents false triggering). The light is separately powered and switched by the trigger circuit.
Tony

Bill,

a. Try adjusting the idle mixture screw. If too closed it may cause the surging. Don't know for sure, though.

b. Buy a decent timing light. Toss the old one.

c. If the timing light is good then the 6 volt battery will work. It's just a tad dimmer is all. If you can't see the flash against the timing hole then throw a blanket over yourself and the engine to block any excess light. May help. Just don't let the blanket get tangled in the fan or pulleys. Also, make sure no one is around to witness you doing it.

d. Call on a friend to help you out. Two minds are better than one on this sort of thing. Tell him that if he'll bring his timing light that you'll furnish the suds. Buy cheap suds.

f. Sell that aggravating car or truck or whatever that thing is. It will always be a work in progress. Well, maybe.

g. Question that newly rebuilt carburetor you just installed. There's rebuilds and then there are rebuilds. Not all are the same. It may be defective.

You're welcome,
Charlie

A 12 volt timing light does not work very well on a 6 volt battery....that's why an accessory 12 volt battery is used to power the 12 volt timing light.

I remember back in the good ole days I had a cheapo timing light that had just one wire to hook onto the spark plug and no trigger. You hooked it up and started the engine and it flashed. True, it wasn't very bright, but if you marked the timing marks with chalk and worked in subdued light, it was adequate.

I also had one that plugged into 110 v that was much brighter. Don't know if they are still available or not.

Do inductive pick up lights work okay with the old solid wire?

I have an almost new 6 and 12 volt timing light that I bought about 30 years ago. It works great on 12 volts and it does work on 6 volts too but it is a little weaker on the 6 volts.