Water pump lubricant additives, any benefit? BobIsTheOilGuy Weld On Seal Lube Gasket Lubricant, NSF Listed, Non Toxic, Non Corrosive, Pint Harrington ProSource 314 481PRO Piston Lube 4 oz A mechanical seal is used to prevent fluid leakage between a rotating shaft and a stationary housing (like in water pumps, oil pumps, compressors, etc.). It works under pressure, temperature changes, and