I recently purchased a B2400 and, long story short, I'm convinced the lift pump is bad. I replaced it, and the new pump worked fine for about 4 hours, and now it failed again. The fuel filter has been replaced and air bled from the system. The tractor will run fine for about 5 minutes, and then loose almost all power. This is with the tank 1/2 full. If I fill the tank, then it works fine. Thus, I'm convinced it's the lift pump. Apparently the lift pumps are a common and frequent failure. I'm going to check the fuel camshaft to make sure it isn't worn down, but I'm tempted to replace the mechanical lift pump with an electric fuel pump. Has anyone ever done this and/or have suggestions on how to do this?