Wont stay lit. I have the heater that will burn on diesel or keroseen. When I turned it on this

Question

I have the heater that will burn on diesel or keroseen. When I turned it on this year it started but after a few minutes of running it quit and blew a big puff of smoke. I turned it off and it did the same thing. I cleaned all of the fileters including the fuel filter and still the same relult. Any help would be appreciated.