Timing Light

[Rob A]

I have hit & miss engines, some of which use the Ford buzz coil for ignition. I have designed and built a LED timing light that runs on a 9V battery and has a clamp for the spark plug wire. The buzz coil produces a bunch of sparks when activated, but my design will only flash on the very first spark. Would there be a use for this on checking the ignition timing on the Model T Ford engine? It would show if each coil is firing at the same BTDC value.

[Humblej]

No, not useful for a model T.

But for those that do not understand the T ignition system, they will probably buy them like hot cakes and you will be rich beyond your wildest dreams.

Am I responding to a bot?

[AndyClary]

It’s an interesting concept. The same thing can be accomplished by wrapping aluminum foil around the plug wire and using a standard timing light. Been doing it for years.

Your results may vary.

Andy

[Rob A]

Thanks for your replies. As opposed to the ECCT, which I greatly admire, (albeit a bit expensive), my tester would show small differences in the timing output of the coils while they are actually operating from the magneto/timer in a running car. This would not only show differences in the coils themselves, but also show effects of timer irregularities. You would need to mark the fan pulley with a mark for TDC. It would also uncover occasional cylinder misfirings. A simple automotive timing light would fire repeatly as the buzz coil fires multiple times, which makes it unusable for buzz coil systems. My tester only flashes on the very first firing and ignores the rest of the firings from the buzz coil.
BTW, I owned a '14 T, so I am familiar with them.

[Adam]

Does your Model T have a functioning magneto and do you run it on magneto?

[John kuehn]

It goes back to recognizing that Model T’s are 100 yr old technology. No computers, no intricate electrical circuits, no warning lights, no GPS. Using your own eyes, ears, nose and common sense will keep your T running just fine. And of course reading and studying the Ford service manual. No kidding .

[Art M]

Andrew,
Your method of wrapping aluminum foil around the spark plug wires when using a standard timing light integers me. I understand that the timing light doesn't see the secondary coil firing.whenBut, I don't understand how the aluminum foil does this. I am not an electrical engineer but have a fairly good understanding of electricity.

With your method of evaluating coil characteristics, I will be able to semi-retire my dual channel oscilloscope by using my timing light. I am anxious to try the foil when the car comes out of winter hybrination in the spring.

Art Mirtes

[speedytinc]

I would encourage you to bring such an item to market. More the better in having affordable diagnostic products available.

I have used a modern timing light. I didn't notice multiple sparks/ light fires. Maybe they were not noticeable due to the motors running speed.
(no wrapping with foil needed)
You would need to mark your pulley @ tdc & 180 also to view cyls 2 & 3.
The light will show firing variations & misses, but how do you distinguish the error in coils, timer or combination of both?? - By switching coils around to confirm or eliminate timer error? Can you easily determine which is the fault?
I have used the timing light to check accurate timer firing by using a fresh ECCT tested set of coils. Good test to find variations in an anderson type timer to determine which contact(s) needs tweaking.
To check the coils alone I would use a known perfect timer unit. That can be tricky also. Is the fault in the timer and or brush contacts, the centering of the cam cover or a dirty timer?

Anyway, carry on. Maybe I gave you something new to think about.
Think about including a comprehensive set of operating instructions with the product.

[speedytinc]

It goes back to recognizing that Model T’s are 100 yr old technology. No computers, no intricate electrical circuits, no warning lights, no GPS. Using your own eyes, ears, nose and common sense will keep your T running just fine. And of course reading and studying the Ford service manual. No kidding .

Sure you can operate a T that barely runs, suffers up hills & wont break 35mph.
"Using your own eyes, ears, nose and common sense will keep your T running just fine."
Well, I dont know about FINE, maybe adequate for SOME folks.
I wont judge you. You are free to do as you will with your stuff.

100 years ago they optimized performance the best they could with HCCTs new fangled timers & plugs.

I gotta believe T's fresh off the line ran a whole lot better than they do now on old coils & worn old timers.

Today We have the means to OPTIMIZE our available meager horsepower.
By optimizing my coil ignition system, I was able to gain 10-15% or so in speed, a much smoother running motor(that will equate to longer engine life) & an unknown noticeable HP increase for hill climbing plus, without changing to a dizzy.

[A Whiteman]

Hello Rob, welcome to the forum.

I apologise for some of our less welcoming posts. Ignition timing and testing is a very old chestnut here with varying and (sometimes contradicting) views on how to achieve it and what tools can help.

I am intrigued by your idea (the best are often the most simple) and reasoning behind your device, it is always refreshing to hear from folk with new ways of looking at things.

The T is not too finicky with ignition exactitude. Yes, fine tuning can improve performance, however, it is not in the same league as setting up a Ferrari engine.

While your timing light sounds like it would be helpful, there is probably not a wide demand for it given the manual and gadget methods of timing we use already, but thank you for sharing all the same.

Kind regards

Adrian

[speedytinc]

Yes, there will be those that poo poo your idea/product. So was the ECCT. But the ECCT has proven to be a very effective & real improvement tool for tuning coils for that segment of T owners that care. Its pretty much a given for the Montana 500 boys.(if they want to be competitive)
Don't let a subset of neigh sayers discourage you. Your fresh idea has merit IMO.
Like any new product, a test quantity would be built & marketed gauged for demand.
If it indeed is an improvement over a normal timing light I am in.

[Rob A]

Thanks for all your mostly encouraging comments. I use my timing light on my hit & miss engines to check when the ignitor or spark plug fires. It works with magneto, battery + coil and buzz coil systems. I’m just a hobbyist that came up with an idea that I thought might be helpful to the T community. I have no desire to sell them for a profit. Its very simple to use; just clamp the pickup around any one of 4 spark plug wires and point it at the fan pulley that you added a TDC mark on it. Not sure why you would need another mark at 180°that speedytinc mentioned.

[Art M]

Rob,
Speedy is right, a mark at 180 degrees will check number 3 and 4. The first mark will check number 4 as well as number 1 cylinder.

Art Mirtes

[Rob A]

Yes, now I realize he is correct. I was thinking of my VW Beetle's flat four engine that doesnt have a 180° mark on its pulley.

[AndyClary]

Good question Art, I started doing this when multi spark ignitions came out in the 80’s. The first spark is the strongest and the foil reduces the sensitivity of the timing light pick up so it doesn’t register the weaker sparks. To be honest I’ve only used a light on a T a couple times because there really is nothing to see as the timing is set statically.


Andy

[Art M]

Andy
Thanks for the explanation. I am most likely going to get beat up for suggesting this. That's OK.
The coil dwell can be measured by starting the engine on battery Ignition and keep it running on battery at 500 rpm. Check the timing position and consider this to be zero. Then increase the speed by 500 rpm, which brings the speed to 1000 rpm. With the timing light check the change in the timing. The timing will be later than what it was at 500 rpm. At 2 millisecond dwell, the timing will change by 6 degrees.

Up until now, I was not able to use this method of measuring coil dwell because i didn't know how to eliminate multiple sparking. Now I don't have to use my buzz box/oscilloscope method.

Art Mirtes

[Rob A]

Yes, that is the problem with mechanically generated spark ignition systems. Its a real problem with a lot of hit & miss engines. As the engine speeds up, the timing gets more retarded; not what you want. Ford knew that, so he allowed the driver to adjust the timing at any time. And drivers back then knew how to do it.