Looking up your model, only shows the solid state ignition. I take it your not getting a spark?
Feel free to add pictures if you'd like.
I attached 2 pictures and my best guess is that the red coil attached with 2 screws is just to charge batteries that probably this lawnmower originally had. The lawnmower was a Troybilt with a engine cover that said 7 HP but when I removed the cover I found a 4HP engine Tecumseh Model:nOVRM120. The engine has electric started but I do not know if need 120 Volts A/C or 12 Volts DC to start. Most of this has been cannibalized by someone. Now the engine will not start because it has NO spark. The plug for the electric starter is a "polarized", meaning that the electricity to the starter may need to be 12 Volts A/C but no sure. I need to find that out too, but I cannot find a repair manual or specs to the Tecumseh engine.
I checked ohms at the coil and found this:
1- Between high side to spark plug and ground= 2,800 ohms, so I assume this is the secondary winding.
2- Between the connector tab as seeing in the attached picture and ground= 390 ohms, so I assume is the primary winding.
3- Between high side to spark plug and tab connector at the coil= 3, 200 ohms
The last reading makes sense since the primary winding and secondary winding are in series with the measuring set up since 2,800 + 390 is approx. 3,200 ohms.
Now I do not know if this engine utilizes "Points" to produce the spark and cannot get the flywheel of until I fabricate and adapter. If this engine has "points" I would assume the problem is bad contacts.
Lastly, I saw the "additional" winding with heavier coil copper wire could be just a "charging" system since the coil has one end to ground and the other to a capacitor with a diode in parallel with the capacitor which makes it a 1/2 wave rectifier which is a "charging system".
Anyone with some suggestions?
It seems that I could not understand how to upload the pictures from my computer or something it is not working right. I am a new member.