JD 4440 won't start when hot

Circa 1982 John Deere 4440 - Clicking heard but starter won't spin when hot. After sitting for, say, a half hour it starts normally. Starter armature maybe? Thank you in advance for any input.
 
There's two solenoids involved, one on the front of the firewall ahead of your left knee, and the solenoid on the starter. Either can fail, not to mention the starter itself.

When it won't start, check for voltage on the "S" terminal on the starter solenoid with the key held in "start" and if there's voltage at the lower large post on the solenoid the feeds the starter, and post back.

When working on this stuff, make sure it's in "park" and have a helper in the seat to depress the clutch and turn the key to "start", rather than risk running over yourself.
 
(quoted from post at 07:12:03 07/26/17) I never recommend bypassing the safety for testing, get a test light and go from there.

Test light will only determine if voltage is present but won't determine how much voltage. IMHO there's no harm in bypassing safety devices for test purposes as long as one is ""extremely careful"".
 
Unless you are into replacing expensive parts by trial and error, the ONLY way to diagnose electrical problems is with a wiring diagram and a VOLTMETER. A bad armature is probably the least likely and most expensive part you could replace. Please don't start with that!
 
Common classic symptom when the brush end bushing is just about gone allowing the armature to touch and then stick to the field coils. Need to confirm that massive amounts of current are flowing though or it's likely something else entirely. Common sense placement of a boy scout north finding compass will show such massive current thru a battery cable going to the starter, but influence from starter or frame iron can skew results. $10 bushing might be all it needs.
 

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