To read a freeze plug size chart such as the one featured on the Freeze Plug Factory website, first decide what kind of material to use for making the freeze plug. The first column contains the part number needed to order the plug. The second column is the size of the freeze plug in inches, while the third is its size in millimeters. Columns five through seven repeat the same information listed in columns one through three.Continue Reading
If purchasing the freeze cup on the basis of whether it is concave or metric, the size chart is set up differently. For concave plugs, column one is the part number and column two is the size in inches, while columns three and four repeat this information. For metric plugs, column one houses the part number, column two has the size in millimeters, and column three simply says, "millimetric," to remind the reader that all measurements for metric plugs are in millimeters. Like the other categories, the information in columns one through three is the same as that in columns five through seven.
Freeze plugs are made out of seven different materials, including brass, steel, gold zinc, stainless steel and pipe. Steel and brass are the most popular choices. Steel fits snugly and is able to handle the high temperature given off by the engine. However, it corrodes over time. Brass does not corrode, but its structure is softer than steel. This gives the brass plug a looser fit than the steel.Learn more about Car Parts & Maintenance