Pinning and welding are the two most common procedures that mechanics use to repair cracked cylinder heads. Pinning involves drilling holes that span the length of the crack, inserting overlapping pins into the crack, and then peening over the pins to smoothen the surface. Welding involves heating the cylinder head above the melting point, then filling the crack with or without filler metal.Continue Reading
Pinning is the most common method used to repair cracked cylinder heads because it's easy to do and cost-effective. However, it doesn't add to the structural integrity of the damaged head, because there are still spaces in the cracks that a pin cannot fill. Welding is the much better repair option because it can completely fill any crack or hole in the head, helping to provide structural strength.
Three types of welding can be used to repair a cracked cylinder head: Tungsten Inert Gas or TIG welding, furnace welding and flame spray welding. Aluminum cylinder head cracks are best repaired using TIG welding. Either furnace welding and flame spray welding can be used to repair cast iron heads.
Of the three types of welding, furnace welding is the most difficult welding process to perform because it requires a lot of heat and demands exceptional skill from the welder. Due to the complex nature of furnace welding, certain automotive machine shops have become widely known for providing the service.Learn more about Engine