#1 service GENERAC 45KW Perform an oil & filter change on generator and thoroughly inspect the generator and transfer switch. Thoroughly clean the generator inside & out. Check /inspect the battery, battery water level (if applicable), all wiring & electrical connections. As well as inspect air filter(s), spark plugs, plug wires, speed sensors & all other engine components. Check and record gas supply pressure (if applicable), all regulators as well as the cooling system. Check all external safety shutdowns & sensors Lastly, check all ATS wiring, connections and voltages and then perform transfer test to properly exercise the entire emergency backup system.