I should probably check the voltage at the battery, it is a couple years old (I use a maintainer to keep it up during the winter, oldest battery I've ever had that still works!). Maybe a dead cell?

Check battery and starter connections are clean , all fuses and interlocks sound ?

Just to be sure, go back and make sure all of the interlocks are in starting position. One of the interlocks that get me most frequently is the blade interlock. The tractor will not start if the blade is engaged.

OK I'll report back. Thanks.

tox , actually the seat interlock along with the brake and reverse / pto interlocks also will cause a no start situation as will poor electrical connections from the battery to the starter or a blown fuse as I previously indicated . However even though continuity tested these interlocks can be affected by misalignment of the mechanical linkages being improperly lubricated and positioned with the interlock detent pin .

Well it was nothing that complicated folks. It was just that the mower deck was engaged when she ran out of gas and the lever was still up in that position when I came along and fueled it up and tried to start it. I'm an idiot. I myself never shut it down with the deck engaged, but Mrs. Tox was a bit flustered at running out of gas and just forgot. In my own defense, my big tractor has a throttle lever in the same place and UP is off, DOWN is more throttle, so that lever being UP on the JD didn't bother my highly distracted and sleep-deprived brain enough to alert me.

At least there's a nice troubleshooting guide in this thread for the next person. Thank you all for your service! And now, a nap.

That sounds so familiar.

That is what I was thinking about when I wrote my reply above. I wish I could say I have never done that, and I could if it had not happen at least once a year from the time I have owned a lawn tractor