9N Ignition update

The 2.25 Volts is "Very LOW" should be 2.8 V and is most likely because you have 3 ballasts in the line.

Your Coil Should be OK, its just "over" protected and the current is very low..

Each ballast Resister must measure something or be open. Are they connected in series (like flashlight batteries) ?

Remove the Coil and Connect the Pigtail To Ground (Frame) Top wire connected... Turn on the Key and using your meter measure the voltage drop across (one probe on each side)of each resistor and mark down each.. Also measaure across the coil (pigtail to top)

I don't understand the 11.5 ohm reading... is that the pigtail to the condensor or Pigtail
to Dist CAP connection (secondary) If its the later you are not reading/adding the scale correctly (like 11.5K)

The 6 volt coil is better performing than the 12 volt MHO but you have to get the Ballast Combo correct. Just a EOM Ballast (Standard) followed by a RU-100 or ICR-13 and you should be good for go.

My Email is on post,

It is a 1/2 ohm 20 watt resistor that you make from a Radio Shack p/n 271-131, 2-pack (about $1.68) of 2 ea: 1 ohm 10 watt ceramic resistors. Ya hold the resistors side-by-side and twist the wire pig-tails together, solder, then crimp some terminal lugs on new resistor lead for eazy installation.

Vola', your own custom 1/2 ohm 20 watt resistor. Now yer an Inginneer (grin)

If you're planning to change to a 12 volt frontmount coil, use ONLY my special trick 1/2 ohm coil current limiter. DO NOT USE the "infamous ballast" with the 12 volt frontmount coil. Understand?

Howsomevers..... ya reports 2.25 volts which is too low for an OEM 6 volt frontmount coil and you reports 3 resistors. I'd say thats 1 resistor too many. I don't know why your 12 volt conversion is using 3 resistors, but suspect installer was electrically challenged. If 2 is good, 3 is better? Not necessarily so.

Not certain how or why you report that you can't read any of the 3 resistances, yet you report 11.5 ohm from coil pigtail to distributor cap. How are you doing that? Disconnect your coil terminal wire and try reading the resistances again. Let us know what you read as it can help diagnose your system and get it working for you.

Leave the 6 volt ballast resistor in and remove one of the other resistors. Try one at a time. A good OEM 6 volt coil should read about 3.5 volts at the coil terminal, wheather the battery is 6 volts or 12 volts.

To resistance check a frontmount ignition coil, remove it from the tractor. Connect one ohmmeter lead to the coil top connector. Then measure eather coil contact underneath. The coil primary that goes to the ignition points should read about 1-2 ohms. The coil secondary that goes to the rotor should read about 5000 ohms. There is a major difference between the 2 readings. Exact value is not critical.

If all you get is "zero" ohms, the coil is probably shorted. BUT also the meter just might be out of calibration, double check by shorting the meter leads together. The difference between "zero" and 1-ohm can be hard to discern on some meters..... ..... .HTH, Dell