6v charging system

This tractor has no ammeter,voltmeter, or discharge light.

The system does not seem to be charging. What is the best way to determine if it is the generator, regulator, or battery? Can I disconnect the battery and just put a voltmeter right on the generator.

Lately, after putting the battery on the charger, so I know the battery is charged, it doesn't want to start. The starter makes kind of an electrical pop, but does not turn. If I crank the starter directly from a jumper cable from my truck, it turns too fast and the engine won't start, but afterwards usually the starter button will begin to work. Alternatively, I've several times jumped the 6v system, at the battery, from my truck.

Summary:

Not sure how to diagnose charging problem.
Wondering if I am killing my starter, battery and/or regulator with irresponsible use of jumper cables.

To check if the generator can charge put a voltmeter on the output terminal and jump the output terminal to the field terminal. This will give you maximum field energy and a voltage of 1-1.5 Volts above battery voltage (engine revving and generator spinning of course)If this works, suspect the regulator. The starter problem may be the solenoid mounted on the starter or possibly the push switch but my money is on the solenoid. good luck
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