Q: Cracked radiator

Hi. If you search the web, you’ll find a lot of ways to "seal a radiator" using everything from stop leak to an egg. All of these are bad ideas as they can contaminate and damage the rest of the cooling system. The only way to properly repair a radiator leak is to replace the radiator. If the vehicle has been allowed to overheat as a result of the leak, you’ll alway want to have a block test performed. Overheating can result in engine damage such as a cracked head or a failed head gasket. This test checks for fuel vapor in the cooling system, which would indicate an internal engine leak. A trained professional, such as one from YourMechanic, will be able replace the radiator and check for other components that might have been harmed.