Spark coil preparation?

[jiminbartow]

After a dormancy of 7 years, I will be attempting to start my 1926 coupe in the next few days. The four spark coils were rebuilt and adjusted by Ron Patterson shortly before I parked it in 2015. After 7 years of the 4 coils being in the coil box and not being used for 7 years, is there anything that needs to be done to the coils, the contacts, or the points in preparation for starting after so long? Can the points become oxidized or corroded, which may entail cleaning? Thank you. Jim Patrick

[Matt in California]

Jim,
Yes, the points could need cleaning.

I have some coil that appeared to be NOS from the 1960s. I cleaned up the points and they fired away. (These didn't have the capacitor changed, so that was another project. But if your coil were rebuilt recently that should not be a issue.)

Matthew

[jiminbartow]

Thank you Matt. When you say “they could need cleaning.” Is that just a wipe down with solvent, such as Naptha…or cleaned with solvent on a soft tooth brush? Jim Patrick

[rainer]

I think you could simplify your life...

I would do it this way:

Switch to "Battery" without any gas in the carburetor, so it can not start.

1. Slowly turn the crank until one coil starts buzzing.
2. Let the coil buzz 10-20 seconds,this will remove any oxidation.
3. Turn the crank 1/2 turn until you hear the next coil buzzing. -> Back to 2.
4. After two complete revolutions of crankshaft you have had all four coils in use.

Background:
This buzzing removes any oxidation from contacts, while solvents can only remove solvable debris. And I am pretty sure you didn't pit oil (or similar) on your contacts.
If one coil does not buzz, use a piece of rough paper or thin cardboard. Open contacts by manually pressing down the tongue, insert the cardboard between contacts, release the tongue, then slide the paper sideways several times. This will gently rub off debris. You may also use some WD40 on the paper.
Only in extreme cases you should use super-fine sanding paper (>1200 grit) instead of paper/cardboard, but this leaves fine scratches in the surfaces. Only necessary when contacts are heavily corroded. This scratches will go away with time, the finer the paper, the quicker...
Everything is fine when the coil produces a nice, equal sound

Normally Relay contacts (and the contacts of buzzer coils) are designed to be self-cleaning. This happens because they have very little horizontal moves to each other. They are also rubbing a little bit, not only touching. -> That does the self cleaning.

[Ron Patterson]

Rainer
I think you meant to say in item 4 "After two complete (crankshaft) revolutions you have had all four coils in use"
Ron Patterson.

[MKossor]

Everything is fine when the coil produces a nice, equal sound

Adjusting coils for equal sound (by ear) or equal average coil current (by Buzz box, HCCT, etc.) are indirect approximations for coil firing Time. Internal combustion engine performance depends on accurate and consistent ignition Timing. This is often lost on the Model T engine because they will start and "Run" with a wide variation in ignition timing but with corresponding vibration, surging, and limited power. Unfortunately, many have come to expect and accept this level of performance for an early automotive engine as good performance - Its NOT! There is a Huge difference between a Model T engine that starts and "Runs" and one that Runs Well.

For optimal Model T engine performance, all 4 coils should be adjusted for equal and consistent firing Time by actually measuring and adjusting coil firing Time and consistency. I've also been surprised by how coil firing time and/or consistency drifts with time and usage. So I check my coils periodically and re-adjust them as necessary to maintain smooth, responsive engine performance all touring season.

Good luck with getting your car up and running to your satisfaction. Have a safe and enjoyable touring season.

[Scott_Conger]

Since Rainer was speaking of a single coil, I don't think he was suggesting tuning by ear. I would suspect that his use of the word "equal" would be equated to "even".

[rainer]

As Ron Patterson corrected me: Of course, two revolution (or four buzzing coils). And 1/2 crankshaft turn between coils. I will also update my post. Thanks, this was a mistake by me.

As I understand the initial post, jiminbartow was asking for some sort of »possibly recommendable maintenance« without any need for getting things fixed/repaired/adjusted.
What I described is removing debris in most gentle way if there exists some at all. Even that should not be necessary when the car was stored in dry condition. My Lizzy is kept continuously above +8°C inside a not heated garage. Started on 3rd pull after standing over winter, I tried 3 weeks ago.

Rainer