So my 30yo peerless oil burner which had been blowing a little white smoke each time it fired up is now belching black sooty smoke. (I turned off the power to it). The Petro tech is coming over between 8am and 12pm (it's now 12:09)

Is it likely that I've run out of luck with it? It had been givng me heat and hot water up unitl last night. It seems that there was some sort of leak into it and it would blow a little white smoke each time it fired. Is the black sooty smoke (the inside is covered with soot as well as some soot on the front of the burner) that the problem has gotten to the point that the heat from the burner cant compensate for the water any more?

Any other theories?

Thanks a bunch.