JD L118 battery wont charge

I have to jump this tractor every use - is the alternator bad? Voltage regulator? Just clicks when I try to start it.

How old is the battery? You can have it checked at most auto parts stores. They only last a few years even the bettter grade ones a little longer.

I think there is a 20 amp fuse located near the battery that you should check.

Last, if you washed it the connectors on the engine are in a position to catch and hold water, they may have shorted out the rectifier/voltage regulator.

Battery is new, fuse is fine. Can I check the connectors or should I just replace the regulator? Could the alternator be bad?

Try to clean the connectors, then check voltage again see if it helped.

Now the fuse pops when I just turn the key
Is there a short somewhere? I bought 6 fuses, went through 2 already today. Just turn the key and "pop".

There must be a wire pinched somewhere shorting out the system. You do not have an electric pto so the only wires go to the headlights. Check near the front of the frame by the hood hinge that is a place where they could pinch easily.
Did this new symptom start after cleaning the connectors?
I sent you a PM for more info.