Hi Matheus,

Yes, I tried thinner as well as acetone. I also used WD40 in place of the kerosene and the engine ran well. I don't recall if I used ether or not in the WD40 mix.

By your description of the weather in Brazil, I see that even in cans, ether is not common. Unfortunately, there really IS no substitute for ether. But any engine can be run without it, as in just getting the engine up to temperature along with some overcompression.

I've run 78% kerosene, 20% oil and 2% cetane booster with good results. BUT the fuel mix will depend on the engine. Early, traditional, steel/iron engines should have up to 30% oil. If you have a modern type, ABC engine, then 20% will be fine.

Cetane boosters DO work and it's my understanding that they really don't boost the cetane but act as ignition improvers, somehow.

That is correct, heating up the engine is the key item in getting an engine to start without ether. But after a flight, the engine will cool to normal temps and you must get it hot again. So yes, if your air is hot already that will help but your engine will need to be much hotter than that. I would guess that the engine gets hotter than 100 Celsius.

Right now, I'm in the big city, some 450 miles away from home. I have my computer with me and two small planes. Otherwise, I would go right out and run some engines to see what kind of formula you might have luck working with. But meanwhile, let me know what engine you are doing diesel with and I'll try and help.