Originally Posted by 
mox
				
			 
			The hot bowl engine of which the most widely known as what powered Lanz Bulldogs is  slightly different principle from other diesels.   There  also were single cylinder two stroke hot bowl engines in tractors made by Field Marshall in  UK,  A H McDonald in Melbourne and others.   In these, the lower side of the cylinder head is a hot bowl of cast iron which is not cooled.  Fuel is in injected onto this.  When hot bowl engines was a commonly used,  fuel for them was heavier and blacker than ordinary diesel fuel which was then often described as "distillate"  I recall drums of it labelled as "Diesel Fuel"  A sawmill in Barmah Forest which operated from 1950 to 1990 was mainly powered by a 65 hp McDonald ML.  Apparently for several years owner had an arrangement with a fuel company to keep supplying fuel for it but eventually had to change the injector so it would run on ordinary diesel.  I have seen a report that Lanz in Germany had some set up to run on tar.  Then another that in North Africa during WW2 some Allied forces scored a Lanz Bulldog tractor left by retreating Germans.  Had no proper fuel but plenty of rancid butter and apparently successfully ran it on this.  
The German army also had Lanz Bulldog tractors when they got stuck in Russia  in a Russian winter. To start them was basically the same technique as in very hot climates.  ie Heat the hot bowl to red hot with blowlamp, pump some fuel in with hand primer which operates injector plunger and swing engine to bounce it off compression.  Lubrication in these motors was "Dry sump".  Oil from oil tank was first pumped through bearings and then to cylinder walls, where it was burnt. No oil changes!.  However, in days before multi viscosity oils, was a problem that in very cold climates, cold oil could make engine difficult to turn when trying to start it.  Solution to this was a while before stopping engine and leaving it overnight,  to run oil mixed with petrol in its lubrication system. Worth noting that Germans in Russian winter apparently largely started their Lanz Bulldogs first in mornings.  Then used them to tow start other vehicles.