I have an old Weil McClain oil burner and the fuel pump trips about twice a week. I had it serviced and its still the same. When I push in the pumps button then hit the transformer reset button it fires right up and doesnt burble too loud or have a fuel smell like it was loaded up with fuel which tells me its starving of fuel then trips. Im a novice so bear with me but could it be anything else besides the fuel pump itself? Anyway to test the pump? How hard are these to swap? I already put a new control box in it 2 years ago so I doubt its electrical.