12 volt coil issue revisited

I replaced the 6-volt coil and ballast resistor with a new 12-volt coil that does not require an external resistor. The tractor cranked and ran great as it did before.

My question is, do I still need the "Dell recommended" 1/2 ohm, 20 watt resistor with the true 12 volt coil? The alternator does indeed put out about 14.5 volts. Thanks.

Rick H. Ga.

My secret trick 1/2 ohm current limiting resistor is for ONLY the modern 12 volt SQUARECAN ignition coil used on the FRONTMOUNT distributor on the 9N/2N/8N flathead 12 volt converted engine.

The un-converted 6-volt frontmount ignition coil still requires the "infamous ballast resistor" and NEVER the secret trick 1/2 ohm resistor. Understand?

Your 4-cylinder NAA Jubilee OHV engine has a roundcan ignition coil and a sidemounted distributor with a 5-nipple cap. They make real 12 volt, NO RESISTOR NEEDED, roundcan 1-nipple ignition coils. Continue to use one on your 12 volt converted NAA electrical system with NO resistor..... ...respectfully, Dell

Unfortunately, you don't provide me enuff information about the component parts of your IGNITION system. ...but... it sounds like your description of diagram using "2 resistors" is the normal 12 volt conversion scheme using the 6-volt squarecan ignition coil plus its manditory "infamous ballast resistor" AND a 12 to 6 volt coverting resistor connected in series like flashlight batterys.

And since you claim when you wired your 12 volt conversion per the drawing and it wouldn't start, my guess is that the squarecan ignition coil was a supplied modern 12 volt squarecan ignition coil and it just plain won't work on the approximately 4 volts the 2-resistors supply. (ALTHO the OEM 6 volt coil works quite well with that resistor scheme and 12 volts)

And I can't begin to guess about the "kit-supplied" resistor, but I can supply some direction there.

A 12 to 6 volt converting resistor will have about 1.5 to 2 ohms resistance. The recommended 12 volt squarecan current limiting resistor is 1/2 ohm. Now most ohm meters don't measure low values of resistance very accurately (its a technical thing) but we looking at 3 to 4 times value of difference between the 2 types of resistors. So measure your kit resistor. Sometimes they even have the ohm value printed on the sides.

Also measure the ignition coil primary resistance. Simplely connect one ohmmeter lead to the squarecan top terminal and measure the resistance to both bottom terminals. The high voltage secondary will read about 7000 ohms for eather the 6 or 12 volt coil. The 6 volt primary will read about 1-ohm. The 12 volt primary will read about 3-ohm. Again major determinate differences.

Once you know the kit resistor value and your frontmount coil primary resistance, then you can determine what to do about the your current ignition coil wiring..... ..... respectfully, Dell a 12 volt advocate for the right reasons

For some reason, the makers of the Ford "N" series 12 Volt replacement front-mount coils just can't seem to get their act together, and make a coil that can withstand the voltage of a modern 12 Volt conversion, without the need for a resistor.

Dean

Those ballest by-passed ignition coils are really designed to provide optimum sparkies on about 8 volts and even a near-death 12 volt battery drugged down by starter load is gonnna be close to 10 volts. Wow, 10 volts onnna 8 volt coil is gonnna really supply HOTTER SPARKIES for the 5-10 seconds it takes to crank and start the modern 12 volt engine before the ignition switch operated resistor by-pass is back in the circuit supplying 8 volts for the ignition coil. Your theory is right but your understanding is not quite. ..... ..respectfully, Dell a 12 volt advocate for the right reasons.

That said, I haven't found the right reason for my eazy starting 6 volt 52 8N, and I know how to do it right, the first time.