Just a reminder or maybe a lesson to new owners. If your tractor goes into loss of power, stumbling, and smoking mode, you will want to perform a couple maintenance tasks to get them running correctly again. First, change the fuel filter on the right hand side of the motor. This is sometimes called the secondary fuel filter. Why you may ask? Well, there is a strainer in the fuel tank. This is often over looked. I have read and seen where some who experience this symptom change the secondary and everything seems to work fine for a while then the problem returns. I use "on road diesel" as I pump my stock into my trucks also. Don't make the mistake of thinking if you use "on road" it won't gum up.
I recently ran into this issue with mine. Got so bad it wouldn't even start. I pulled the strainer out of the tank and it was completely plugged. I drained the tank and with a very bright flashlight I inspected inside the tank. I had a garden growing in the bottom. lol Upon further inspection I was finding a ton of rust bits in there also. Yep, you guessed it. The little chain they put on the fuel cap rusts away in about a year and all that crap drops right into your tank. I managed to rig up a swab on the end of a metal rod and wipe the inside out. I then took an extendo magnet and got the rest of the rust bits out. Get both pieces of that old rusty chain out of there and replace with a heave cord of some type.
This is after only 450 hours of use but my tractor is over 4 years old (yes, I have other tractors). I have used the diesel additive and my storage tank has a Napa fuel filter on it.
So, just a heads up. If you plan to use it and can't afford the down time. Try this routine maintenance and save some aggravation.