Never Ever hook up city water Hose
City water Pressure may overload the ability of the waterlift muffler toexpell the water. The water will build up in the muffler and then back up into the cylinders. Hydro lock, thrown Rod. A five gal bucket with an overflow hole cut a few inched down from the top will prevent unwanted hydrolock. Run the Engine. Run the hose nozzle, filling the bucket, at a rate which causes some of the water to overflow into the bilge. The bilge pump will pump it out. Have the intake water hose draw water from the bucket. Let the engine get hot, this insures that the thermostat will open, important for boats without heat exchangers. After 15 min or so switch the hose to an open full antifreeze bottle. Use one or two bottles. Cut engine before all antifreeze is expelled.