Won’t turn over after RPM gauge dropped mid-hay season

[BattleCattle16]

My dad's Zetor 6341 was running fine while baling hay in northern Indiana. RPM gauge dropped to zero suddenly, engine still running. He shut it off, and now it won't start, no lights, no crank. It's hot and humid, and we're behind on hay. Could this be a fuse issue or something with the alternator?

 

[ddu-ddu-du]

My dad's Zetor 6341 was running fine while baling hay in northern Indiana. RPM gauge dropped to zero suddenly, engine still running. He shut it off, and now it won't start, no lights, no crank. It's hot and humid, and we're behind on hay. Could this be a fuse issue or something with the alternator?

Actually, that sudden RPM drop with no lights or crank feels like a main power issue. Check the main fuses and battery connections first. They're the first ones to usually take the hit before the alternator.

 

[GreatBruce]

Could the sudden loss of RPM signal and no-start condition be caused by a blown main fuse, or might the alternator or ignition switch have failed under the hot, humid conditions?

 

[BattleCattle16]

We finally got around to checking the basics last weekend. One of the main fuses was blown, which got the dash working again, but the crank is still acting up. We're focusing on the ignition switch and alternator wiring, since the RPM gauge dropped and the tractor wouldn't start right after a long run in hot, humid weather. If the heat affected the switch or alternator, that might explain why it failed later. We plan to test both this week and hope to have the tractor running before the next rain. Has anyone seen the ignition switch fail slowly, or does it usually just quit all at once on the 6341?