Raider 8 green wire going to start switch smoking and red hot

[Wendelin Giebel 4]

My Raider 8 ignition key switch is red hot. The green wire ( amp meter ) is burning its insulation . Tractor starts and runs as usual . Would anybody like to offer an opinion . I have noticed the wire connector on wire appears dirty but I hesitate to cut it out and replace until I have more evidence that’s the problem. Wondering if this is symptom of a bad key switch , amp meter seems to be working as usual? 

[WHX?? 57,496]

Most likely the amp meter is grounded. Disconnect it and tie the wires together that were on the posts and see if the wiring continues to get hot. Check the posts on the meter to see if insulation has broken down. 

[ri702bill 12,562]

Welcome!!

A lot of WH models from the '60's and '70's did NOT come with an inline fuse on the red wire feeding the ammeter. I always add one on all of mine. Nice to have when there is a short in the wiring, or either the keyswitch or ammeter go bad. Also, check the condition of all your terminal connections. Rusted or corroded terminals raise the resistance, lower the voltage, and turn the wiring into a space heater....

Edited 52 minutes ago by ri702bill