77 is a premium cast iron welding rod that produces machinable welds which are high strength, crack resistant, and porosity free when applied to a wide variety of cast irons. 

Cast Iron Welding Rod Key Features:

• Developed specifically for maintenance applications
• Welds all types of cast iron, thick or thin
• Good color match to cast iron
• Crack-resistant formula eliminates the need for pre-heating or special cooling
• Works in all positions, including overhead
• Coating is electrically conductive, eliminating core-wire overheating
• High deposition rate, fluidity, and even heat conduction create fully machinable welds
• Special formulation compensates for shrinkage as the base metal cools, eliminating the contraction that can cause cracking
• Ideal for heavy machinery, trucking, bus lines, automotive, marine, and RVs
• Repair cast iron exhaust manifolds, engine blocks, transmission housings, cylinder heads, industrial machines and more

Note:  Drill holes at each end of the crack, then align the parts if necessary and tack weld. Guide the electrode at a steep angle, keeping the arc length short.  Use short staggered passes.