Jerry - I guess if one had nothing else..........................
When I was stationed in Japan more than 50 years ago, would occasionally see three-wheel pickup trucks with part of the bed taken up by a "double boiler" (don't know correct name). They had a fire in the lower section, with green wood in the upper section. The fumes from the upper section were piped to the engine. Not sure how well it worked, but it did work. I have wished many times that I had looked at the engine compartment of one of those trucks.
Jon.
