I will run out of diesel before I find out… It shouldn’t need any more cleaning than any other stove if you keep it clean by priming carefully with alcohol then flipping and shutting the valve when the flame dies…poor priming will soot it up. I still mess up the priming sometimes and that results in soot. So far the jet has remained clean and it hasn’t blocked in maybe six or so burns. Short answer diesel is as clean as your technique allows.
I'm finding diesel to be a pretty good fuel now that I can use it with just as much cleanliness as any other fuel. I timed the priming with alcohol...twice...to be sure to be sure...2 minutes is close to the mark. Not too bad but with diesel you don't want to under prime the stove else you get a big yellow and dirty fireball although it can be nursed into a good burn anyway. This fuel seems hotter to me than Shellite or Unleaded. I will do some more testing later but diesel is quite nice to use but not if you have to prime with it as it will produce prodigious amounts of soot if you do that and that coats everything including the jet. I just got my XGK Expedition Service Kit today from Amazon so I will be putting the shaker needle and fuel filter back into my Dragonfly. Disclaimer: Testing done at 25 C and 30 m altitude here in Perth Australia...so if you are on Denali and using Diesel in the XGK unsuccessfully and are about to die...don't say I told you to use diesel on Denali! My guess is diesel would work well into minus F but I don't know for sure although I'd be sure kerosene will operate into minus F. Diesel is an interesting substance and quite oily with quite a high viscosity and hence the need for its own jet on the XGK. I might top up on diesel and continue to use the stove on diesel I think as it is so cheap and it burns hotter than naptha which I like.
I just used BP Premium Diesel from the pump...it was the only choice I had so that made it easy. This is Australia too but diesel will be similar that powers vehicles in other countries. It is at least only 10ppm sulphur unlike unleaded 91 here which is 150ppm sulphur...95 drops to 50ppm but that still seems a lot.
Diesel has been a success in the XGK. The XGK has definitely lived up to the burn anything (within reason) reputation. That nice big generator loop keeps it hot which is definitely good for heavier fuels and for that matter any fuel but I can see why this XGK excels in difficult conditions. Priming and good shutdown technique can totally sidestep soot production. I have measured alcohol for priming and it takes about 5 grams of alcohol and about 2 minutes to prime properly. Do it properly and no soot. Flip the bottle for shutdown. The conclusion is...for the XGK I'd much rather use diesel than unleaded petrol as it burns hotter and has fewer additives. The downside is you have to be careful with priming and please do not spill the diesel...
