If your tractor has a fuel pump, don't worry about the fuel filter if it only has a bit of fuel in the bottom, you cannot judge what you engine is doing by what you see in the fuel filter.
Visually check fuel output from the pump to the carb spraying into a coffee can or similar.
There are test procedures and gages that can help you, but once you buy a few gages, JD dealer might be a better answer.
If pump output looks good (your opinion-my tractor uses .9 ounces per minute), move to the carb.
Remove and examine the float bowl, wipe out any dirt from the bowl, blow clean w/air. (you may have to remove carb to get float bowl back on.
While bowl is off, check float (in the bowl chamber), but above where the bowl had been removed.
Make sure the float moves freely as this is the main fuel jet. If you were actually starving for gas, I am not sure the float is the issue unless it is stuck in the closed (all the way up) position.
After all that is done and the engine still doesn't run well, try this~~
Find the low speed screw on the carb (this is the only air screw that is adjustable on 14 HP Kawasaki and turn 1/4 to 1/2 turn counterclockwise.
If that works, you may run the tractor for (maybe_ another 6 months, but I am guessing a carb clean.
Saw on this site or another Seafoam, never used it, but had to go through the above troubleshooting proceedures on my 14 HP with good results.