1Volt at Coil

[tinner666]

About 1950 8N. Replaced harness, resistor, coil, regulator, etc. Full continuity down the wire, 6V at switch, resister, etc.
Could there be a short in generator causing this? Reversed wires on generator?
Bound to be something simple.

 

[EdGooding]

Do you have the front-mount distributor with the coil on top of it?

You said you replaced the resistor. The one that attaches to the back of the dash panel?

Where did you measure the 1-volt? On the other side of the new resistor or at the coil?

The 8N has three circuits: starting, charging, and ignition. Your generator charges your battery and has nothing to do with your ignition system. If your battery is charging at around 7.3 volts with the engine running, then your generator and voltage regulator are working fine.

 

[ruffdog]

Is the tractor positive ground and are all the components wired correctly?

 

[Roadworthy]

Do you have one volt at both sides of the resistor or just one? Were the points open or closed when you took your measurement? When the points close they ground one side of the resistor - that's what makes the spark. Your points need to be properly adjusted to work.

 

[tinner666]

Do you have the front-mount distributor with the coil on top of it?

You said you replaced the resistor. The one that attaches to the back of the dash panel?

Where did you measure the 1-volt? On the other side of the new resistor or at the coil?

The 8N has three circuits: starting, charging, and ignition. Your generator charges your battery and has nothing to do with your ignition system. If your battery is charging at around 7.3 volts with the engine running, then your generator and voltage regulator are working fine.

Yes to your questions. Was curious about generator because new regulator has different configuration than old and may have field wrong.

Continuity checks out on resistor and coil wire, end to end. 6V on both sides of resistor.
At coil, voltage test shows 1v at coil terminal. I believe there is a short in coil at this point. Spinning starter doesn’t change anything.

 

[EdGooding]

The front-mount coils are problematic, especially the new ones from the "land of almost right." Napa sells one that is a little better quality. If you have not been feeding the right voltage to the coil, you can easily toast it, so replacing may be your best option at this point.

For your regulator, here's a wiring pictogram to show how it should be wired: