Maxi fuse keeps blowing as soon as I put it in. Key is off. Stator and regulator are good. Starters good. All other fuses are good. How would I go about locating an electrical short? 05 sportster

 

You need an ohmmeter.

Disconnect the battery.
Take out maxi fuse.
Measure with ohmmeter from each side of fuse carrier to ground. To blow the fuse one side must be near 0 ohms.
You will need to start disconnecting things from the side where you see the low ohms.

There is a very similar thread I saw the other day and it turned out to be the regulator.

 

Check the wires between the maxi fuse and the voltage regulator.

See if the fuse still blows when the voltage regulator is unplugged.

Check the wires between the maxi fuse and the fuse block.

Check the wires between the maxi fuse and the ignition switch.

 

So everything is fine, you slide the key into the ignition and the fuse blows without turning the key at all?
If so I would start with the ignition, you might have something shorting internally in the ignition switch or the wiring directly behind it.

 

A clever trick to troubleshoot a dead short is to temporarily wire a low wattage 12 volt bulb in place of the fuse, it will glow brightly so long as the short is present and will limit current i.e. a 12 watt bulb will only conduct about 1 amp, etc...
When you fix the short the bulb will go out or maybe only glow dimly.

 

Thank you. I followed the voltage regulator wire and it appears melted... So I disconnected it and the maxi fuse is fine. Ordered a new voltage regulator.should I replace stator a well?

 

Not unless it tests bad, I think there are instructions on testing it in one of the stickies at the top of the page.

 

Why did voltage regulator wires melt would be first step.
Stator side, battery side ?
Is a connector bad?
A stator can be tested as AC voltage not DC voltage with a meter.