I wouldn’t recommend using anything to “start” your diesel other than diesel!Thanks. I actually made a little progress on the generator. I could get it to run slightly on wd40 and a dash of carb cleaner. It wouldn't stay running for long, though. I like your idea, but it is now leaking fuel and coolant, so it needs some attention all over.
carb cleaner will wash the cylinders clean and dry and , like starting fluid , will make it harder to start for ever!
pull the fuel filter, if it’s got black goo in it then you have algae as we mentioned. I suspect you will find it is the fuel pump, crack the injectors and crank it over and see if you get any diesel leaking out of the injector lines.