4. Fog the Engine(s)
With the boat hauled, fill a remote fuel tank with five gallons of gas, two quarts of TC-W3 two-stroke oil (even with a four-stroke) and five ounces of fuel stabilizer. Connect the tank and, using a motor flusher ("earmuffs") over the water pickups, run the engine for five minutes at about 1,000 rpm. Shut it down and replace the engine oil and oil filter (if it's a four-stroke) and lower-unit gear lube.