Tractor Repair: battery dies on tractor, blown fuse, amp meter

Question
I have a JD 4310.  Battery kept dieing after charging.  checked alternator and it was bad. had it rebuilt.  battery would still not hold charge.  checked battery, it would not hold charge.  got new battery.  it started tractor 3 times in a row. (yah!!)  I let tractor sit for @2 hours with new battery and then battery was dead.  charged and started tractor, but I'm sure it will be dead at next use.  No switches are left on and checked all other possibilities.  There is a 20 amp broke fuse that I assume goes to the front lights since they stoped working a few months ago.  could that be what is causing this battery leak? I plan on replacing it this weekend.  HELP PLEASE!

Answer
Hello,

  I know this will sound stupid, but first check that the battery polarity is correct, negative ground , and that it is the correct battery for this machine.   Anyone can make a mistake no matter how much mechanical experience they have, so we have to start with the basics.  
  If there is a current draw that big, it should make some pretty big sparks when you attach or remove the cables at the battery, so be very careful and wear safety equipment because a spark could cause a battery to explode.
  A blown fuse will shut off power to that circuit, so the problem should not be in the light circuit, however you are assuming it is for the lights and possibly it is not.   Replace the fuse first and then continue testing.  Here is the most logical testing sequence because it starts with the most likely causes first.  Remove the negative cable (ground) from the battery and hook up a test light or amp meter (not volt meter) between the cable terminal and the battery post.  When something is drawing current, the light will light up or the amp meter will show amperage.  Remove the fuses one at a time until the test light goes out or the amp meter shows no amperage.  The source of the current draw is on the circuit for the last fuse that you removed.  That way you will narrow it down and know what circuit to check for problems.   If the draw is still there with all the fuses removed, then disconnect the alternator.  Even though you had the alternator rebuilt, there could still be a problem with the isolation diode.  If it still shows a draw, start disconnecting wires on the machine until the draw is gone.  If you follow this procedure, you will eventually find the source of the problem.

                         Good luck,

                               Arnie