A fuel pump on a John Deere tractor has a sensor that helps regulate fuel flow into the carburetor. If the sensor is not working properly, the pump will not give the engine enough fuel to run, which causes the engine to backfire and randomly shut off. No electronic tools are needed to check the pump's sensor and the process to check the sensor takes about 15 minutes, so you will know soon if your pump needs to be replaced.
Drive the John Deere tractor onto a flat surface.
Pour gas into the tank if there is not any in the tank.
Slide a pan underneath the engine.
Pop the hood open. Find the rubber fuel line on the side of the engine. Follow it until it goes into the carburetor in the engine. Unplug the pins on the line and the wiring on the line.
Place an alligator clip on the (+) part of the battery. Connect the other clip to one of the places where the wires were connected on the fuel line.
Connect the other alligator clip from the (-) part of the battery to the other wire connection on the fuel line.
Drain the fuel into the pan. Look at the fuel coming out of the line. If the fuel is pumping out very fast, the pump is working correctly. If it is just trickling out, the pump needs to be replaced.