Radiator sealant is a liquid mixture that is poured directly into a radiator to stop leaks in an automobile's cooling system. When used according to the sealant's manufacturer recommendations, radiator sealant is safe to use to stop or prevent cooling system leaks.
Car owners should read carefully the sealant package to make certain they are using the proper type and amount of radiator sealant for their vehicles. When using radiator sealant, the heat control in the vehicle should be turned to hot. This will allow the sealant to flow through the heater core, treating it for leaks and preventing the solids in the stop leak from building up in the heater core's intake lines.
Radiator sealant is designed to stop small leaks in the cooling systems from pinholes in radiator bodies, heater cores or freeze plugs, as well as small leaks in gaskets. Radiator sealant can be used to stop current leaks in a cooling system or to prevent the development of leaks.
Radiator sealant can fix some minor cooling system leaks, but other leaks will require a physical repair. Leaks from worn water pumps will require replacement of the pump. Large internal engine leaks caused by blown head gaskets or cracked heads will also require physical repairs.
