Small Engine Troubleshooting Problems? Ask a Mechanic Now.
Where is the fuel shutoff solenoid? Unplug it and flip key on to see if the fuse blows. Fuel solenoid comes on as soon as key is turned on.. Next would be to unplug the voltage regulator .
What engine do you have? It may be part of the alternator.
It has alternator with built in regulator. you would have to remove field wire from alternator, or just unplug the alternator.
!! You will just have to isolate what wiring section causes it and then check each wire to find the source of the short. With all the usual ones out of the picture, not sure what else to try.