I have been battling this problem for almost two years now. What happens is the tractor runs great and then randomly it sounds like it is starved for diesel and the RPM drop and although most times it will not stall completely, the tractor has very little power. If I wait a few seconds the engine comes alive again and all is well until next time. It seems to only happen when the tractor is cold. Once the tractor warms up significantly or the weather is better I don"t have the problem. I"ve tried diesel additives in the diesel tank and the tractor, which have not helped in any way I can notice. The main thing that helps for any significant time is changing the fuel filters. I think I"ve changed about 12 in the last two years (not ideal). Anyone got an idea or two?