I have a Sears lawn tractor with a 17 hp Kohler engine.
It starts fine and runs fine for a while. The clear fuel filter is about 3/4 full and gas iss flowing fine.
Then after awhile the engine starts to putter, and the fuel filter is almost dry. Then it stalls, and the fuel filter barely has gas in it for as long as I run the engine after restarting.
Very odd. Thanks

Most fuel filters do not have much fuel visible when the engine is running. I've seen them run and not see any fuel at all in the filters, you don't have to have an abundance of fuel for a small engine. Your problem is either the fuel pump or carb is dirty I would suspect.

I would start with the fuel pump

This is a classic symptom of the vent being plugged in the gas cap. Check the center of the cap for a vent hole. It is likely plugged. Take a pin and break through the dirt and then blow into the hole from the top of the cap to ensure that air is getting through.