Never say never without knowing history. I usually like to study it before doing any new project.
From the ag machines we had going back to around 1930.
Old Monarch or Allis Chalmers. Semi - Diesel with plugs. Others out there but we did not have them.
International Anything with D in the second letter of the model. ie WD, MD, TD had a diesel. We got our first in 1938 when the second generation came out as a TD-14. Had plugs and a carb on one side of the engine and the diesel injectors and pump on the other side. We had MDs, WD-9s, TD-9s, TD-14s and T-18's. They also could be cranked if the battery was dead. The 18s where huge 6 cylinder models. The others were 4 cylinders. My uncle who was about 100 lbs taught me how to crank an 18.
John Deere and Cat had pony engines that were gas. They worked but did not start as well as the internationals when cold. You cussed on the D-4s and D6s trying to get them going.
We did not have them but I am sure Buda and Waukesha had some diesels with plugs too.
I once got a comment from an engineer working on a hydrogen engine it ran but was destructively rough. I looked at him and said have you tried injecting water. He looked at me like at me like I had 7 heads. I said ag engines have been doing that since the days of Hart-Parr. Some old fighter engines did it too. He did get it to run right a couple years later with a water injector. Knowing about how Hart Parr went to a water injector after a farmer spilled liquid that ran into his engine found it ran better ran than damaging it. It is easier doing things knowing history.
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