Bar’s Leaks Radiator Stop Leak seals internal, external, and coolant-to-oil leaks in your vehicle’s cooling system. Specially formulated to work safely and effectively on plastic, aluminum, and metal radiators, heater cores, blocks, heads, gaskets, and freeze plugs. Compatible with both conventional silicate-based and extended-life (OAT/HOAT) antifreeze in all types and colors, and can also be used in straight water. Pre-dissolved pelletized formula installs easily — simply pour into the radiator or coolant reservoir. Also lubricates the water pump seal to inhibit rust, scale, and potential future leaks.
- Seals internal, external, and coolant-to-oil leaks
- Compatible with all antifreeze types and colors (OAT/HOAT)
- Works on radiators, heater cores, blocks, heads, gaskets, and freeze plugs
- Pre-dissolved for quick, easy installation
- Lubricates water pump seal; inhibits rust and corrosion
- 11 oz. bottle treats one cooling system