A few observations by a diesel compact diesel tractor and multi diesel vehicle owner. We have a pre emission 10 + year old Kioti which was my introduction to diesel ownership. We have also been through 8 VW diesels all 4 cylinder turbo diesels ranging from a 2006 through 2014. I do all the maintenance an most of the the repairs on all of them. that said I find the Kioti very primitive it has no DPF, egr, or cat. I have only had problems with what I believe was/is a defective or poorly designed hydraulic pump driven off the engines cam. I would definitely drain the tank and change the fuel filter if any more than a pint of gas was dumped in simply because the tank is only @ 5 gals and it would be so easy and cheap, why take the risk for so little work. That said if I contaminated a new tractor with any emissions, electronics or high tech fuel systems (high pressure fuel pumps, DPF’s, o2 sensors urea injection etc.) I would be very cautious. Gas was put in my daughters 2006 VW golf TDI and was quite an issue, she drove until it died and I’d cost me 3 days labor and about $800 in parts to repair (had I not towed it home and repaired it myself the estimates were $2,500 -$4,000) In the new on road emissions controlled diesels there are numerous problems with gas in the fuel including the lack of lubricity destroying the high pressure fuel systems and causing thousands in damage. I can only imagine what gas might do to the diesel particulate filter, Cat, or the egr system. The problem of fuel system contamination is so serious that in Europe where it is far more common due to a much greater % of diesel passenger vehicles that there are specialists who drive sprinter vans and do road service to drain fuel systems on site & clean out fuel systems. These services have Contaminated fuel recovery tanks, special pumping equipment, tools and replacement fuel filters for most cars. The service is $$$ (I say an article quoting 500+ Euros almost 10 years ago, and no guarantee it would work) and they claim to be able to prevent any damage if the car was never started and could save most vehicles if they are driven only until the vehicle 1st gets the contaminated fuel and stalls. I know the VW and Audi considered the problem so serious that all our VW TDI’s from 2009 on will only allow the specific bore of diesel pump designed for diesel passenger cars. I you attempt to fit a unleaded pump into the filler neck the flap will not open and it will not go in I only know this from being at some very rural stations in GA and the Carolinas that have had old unleaded pump nozzles on their “car” diesel pumps and we could not get fuel because the big “truck” bore pump nozzles were simply too large to fit in the filler neck and the old “unleaded” nozzle was slightly too narrow to trigger the flap mechanism to open. We still have four TDI’s from 2011 through 2014 and they all have the neck that accepts only passenger vehicle highway diesel only. I actually bought and carry big bore adapter kits for each vehicle to allow filling with a big bore truck stop pump in an emergency. My point being that running gas in the new epa emission compliant diesels is a serious problem, as is the right to repair issue with all the electronics. I have a $500 VCDS computer interface specifically for VW just to be able to diagnose and work on them. The fuel pump systems are so delicate that you have the use the VCDS to electrically prime the system after changing the filter to avoid damaging the fuel pump at start up. I jump through numerous hoops to drive these cars because they average @ 40 mpg and have a quality ride but if I had to have a tractor with all the ********, electronics, sensors, DPF filters, o2 sensors, and a proprietary OBD system I would definitely pass as I am not a professional heavy equipment operator or commercial farmer who can pass the cost down the line. Sorry for the long winded post but I really feel anyone who has never owned tractor and or a diesel vehicle (especially a epa compliant new one) should be warned. Especially a hobbyist buying a diesel tractor with proprietary on board diagnostics. I am aging out of the tractor market, but I say without equivocation knowing what I know now about diesels, diesel emissions equipment, OBD diagnostics and the right to repair rules as the stand I would never buy a hobby tractor w/o right to repair especially while trying to meet on road type vehicle emissions.