Core Plug

A core plug, also known as a freeze plug or expansion plug, is a cylindrical metal component used to seal holes in the engine block or cylinder head of an automotive engine. Its primary function is to prevent coolant leaks and protect against the freezing and expansion of coolant during low temperatures, which can cause engine damage. Core plugs are typically made from materials like steel or aluminum and are installed during the manufacturing process or replaced during engine repairs. Their design allows them to expand and create a tight seal, ensuring the engine operates efficiently and maintains proper fluid levels.