Bill Esker: High compression to fire an Otto cycle engine is the issue. None have ever succeed so far, because metallurgy has not allowed a light enough high compression engine. GA has made some inroads, they can tolerate some excess weight, but for very light/ultralight we can tolerate no excess weight. But diesels also have fuel jelling issues and do need a battery for both starters and glow plugs. If you have ever tried to pull start a small diesel without those in cold weather, you know exactly why!
Me: Bill, thanks for your answer. I will add it to my page…before i forget it. On the ground the fuel can be heated by outside source (heater or electricity), once turning the fuel might pass the warmer engine and this keeps the diesel nicely flowing, i guess.
About cranking a diesel engine: now i recall why only huge men were truck drivers in the past. :)
Bill Esker: And why diesels have glow plugs and electric starters now!
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