Freeze Plug

Freeze Plug Operation:

Replaceable, round, presized, cup-shaped metal plugs inserted on the outside of the engine block to seal off water jackets and prevent coolant from leaking out of the block. These plugs, also called expansion or frost plugs, can be rubber with an adjusting nut to control the outside diameter and can be made of brass for marine applications.

How To Instructions:

Inspect - Check for obvious problems.
Replace - Out with the old, in with the new.

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