Frost Plugs (Welch Plugs) Metric

Description

Frost plugs are usually thin metal cups press fitted into the casting holes. The most common metal plugs used in automotive engines are made from plated mild steel or brass. The sole purpose of a Frost plug is to literally act as a plug in the holes designed to be in a casting which allows the casting sand to be removed during the manufacture process, coincidental if freezing does occur the frost plugs will be forced out by water freezing inside the block due to a lack of an anti-freeze/water mixture and stop the freezing water cracking the engine block and head.