How To Repair Cracked Cast Iron - Car Craft Magazine

Cast Iron Repair Cracks. They are the bane of all car crafters, and cast iron cracks are among the most difficult to repair. Cast iron repair is really not even something you can do in your own shop unless you have years of experience and the right equipment. The variables of the type of cast iron (gray, alloy, nodular, malleable) and the various types of repairs are incredibly numerous and too complex to get into here. So this story is really about showing you some repairs and a couple of ways to go about them. When it came time to repair a crack in a numbers-matching 396 block for a Chevelle, the call went out to Kelly’s Block Welding in Los Angeles, where owner Garrick Preece and welder Jun Nakawatase applied their considerable cast iron experience to this repair. Check it out.

Lock-N-Stitch Cast Iron Repair

There is another process for cast iron repair that does not involve welding. The Lock-N-Stitch company offers a repair alternative involving a series of interlocking, threaded pins inserted along the line of the crack. These pins actually pull in the damaged section of cast iron as they are tightened. They have been successfully used in both cast-iron and aluminum blocks and heads. If you can access the crack with a drill motor, this process can repair the crack without welding. To learn more about this process and the product, check out the company’s website, which contains several repair examples, including one Cummins Diesel engine that required removing a large section of the outside of the cylinder block and replacing it with a steel plate. It’s an amazing repair sequence.