Sparkless 9n

All sparky coils work the same way.

1) the points must first be closed for the primary winding to generate a great big magnetic field that surrounds the secondary.

2) Then the points must OPEN which allows the magnetic field to collaspe very very FAST. this colasping magnitic field cuts the coils of the secondary, generating a HUMONGUS high voltage that jumps the sparkplug gap thus igniting the mixture with a rush that forces the piston down the cylinder thus turning the crankshaft and vola.....your engine runs.....

3) Since the little spring under the coil is what gets the current to the ignition points so they can do their thing and since you appear to have the ignition coil dangling in mid-air taking your voltage measurements..... .ya' jus' ain't gonna' generate any sparkies to the little ol' clip that goes to the rotor.

4) It takes very expensive Electronic Lab Grade test equipment to check out any ignition coil beyound simple continiuity. And since the ignition coil is an "auto-transformer" winding, any 2 contacts will be continiuous if the coil is good with an "OHM" meter.....N.B. "auto-transformer" is a electrical term and not a tractor/automotive term.

5) Generally speaking, the eazest test for an ignition coil is remove and replace with a known good one..... ...Dell

"Z" or Impedance Bridges which are electronic lab instruments that can measure the inductance of a coil, if you know how to use one. But first you have to know what the specifications of the coil are to know if it is good or bad. The common Volt/Ohm multimeter can only determine if the coil has continuity, not whether the coil sparkies output is good or bad.

Years of experience tells me its just cheaper to bite the bullet and replace the coil given the faults of the ignition system quoted..... .Dell