〉 Answered on Jan 4th, 2013 by Jo An Holt, Automotive Journalist at Holt & Associates
The simplle answer is, no. Coolant additives are meant to seal small cracks in a car's radiator. They may work for a brief amount of time in a car with a blown head gasket, but will soon leak again due to the extreme pressures bleeding from the cylinders into the water system.
〉 Answered on Jan 4th, 2013 by Karen Salvaggio, Owner/ Editor Thunder Valley Racing and Professional Race Car Driver at Thunder Valley Racing
The short answer is no, they do not. Head gaskets typically consist of materials like copper, steel, graphite and polymer coatings. When a head gasket fails it is due to deterioration of these components which creates a sealing void that no liquid sealant can replace.
〉 Answered on Jan 4th, 2013 by Stephanie Gutierrez, Marketing Communications Coordinator at Victory Auto Service & Glass