I have a problem with one of my Victa two stroke powertorque mowers with smokey exhaust filling the yard.
When I tested another one with fuel from the same container, no such problem. It doesn't clear after warming up and I had to shut it down pretty quickly for fear of attracting complaints from the neighbours.
What are the common causes? The smoke is blue as though the fuel is too rich, but the other unit is fine.

Ahh, if only victa had kept producing the thumblatch catcher series, they would be in better shape today!