Alternator damage

[jimjumper-HT]

I should have put the subject as "idiot damages alternator" but. When I changed the battery out I accidentally put it in backwards. After I noticed it I changed it back without starting it but I did turn the key on to check the lights for power, which did work. After reversing it and starting the tractor, I noticed smoke from the alternator. I shut it down and pulled the power lead isolating the alternator. It restarted just fine but when I touch the wire to the connection point it sparks and I would assume the alternator would get hot again. I could replace the alternator since it's probably damaged already but I don't want to just burn up another one trying to figure it out. Any ideas?

 

[winston-HT]

I am ignorant for most part with electrical but my small amount of googling on this matter would indicate you probably blew the rectifying diodes. Maybe take it to an alternator repair shop or maybe make a phone call to one just asking "what have I done" and "could it be repaired"?

 

[jimjumper-HT]

Thanks for the search hint. I am inclined to think you are correct. The schematic I have for the 240 only shows that I have the generator wired correctly (I recently rebuilt the top end and was careful to take pictures of whatever I disconnected) so I assume that since everything else, lights, starter, thermostart, etc. works as long the battery is charged, that the diodes are physically inside the generator and not the regulator? Since the generator is so old, 25 years+, if the diodes are inside I'll probably just replace the generator.

 

[jimjumper-HT]

Never mind the last question. I was looking through the troubleshooting section of the service manual and it mentions generator diodes. So I'll be replacing the generator. In the meantime I'll just keep the battery well charged.