This Spark Plug Thread Repair Kit is a professional-grade tool set engineered to permanently repair worn, cross-threaded, or stripped spark plug threads in aluminum or cast-iron cylinder heads. It is primarily built for the widely used M14x1.25 spark plug thread specification, which fits most gasoline engines in cars, motorcycles, and light trucks. The kit contains one high-carbon steel tap and multiple threaded steel inserts, providing all the core components needed to complete the repair without additional specialized tools.
Key Components & Features
Precision Thread Tap: The black oxide-finished tap is made of high-strength alloy steel, heat-treated for durability. It is designed to clean and re-cut the damaged internal threads in the cylinder head, creating a precise, oversized path for the repair insert. The tap features a standard 21mm hex drive, making it compatible with common ratchets or socket wrenches for easy operation.
Reinforced Thread Inserts: The kit includes multiple galvanized steel inserts, each machined to match the original M14x1.25 thread specification. These inserts are precision-engineered to fit into the re-tapped hole, creating a new, wear-resistant thread surface that is stronger than the original aluminum threads. The inserts also feature external threads that lock securely into the cylinder head material, preventing loosening under engine vibration and heat cycles.
Durability & Performance: The tap’s black oxide coating resists rust and corrosion, while the inserts’ zinc plating provides long-term protection against wear, heat, and engine fluids. The repaired threads can withstand the same high temperatures and pressures as the original threads, ensuring a reliable seal and preventing issues like spark plug blowout or compression leaks.
Ease of Use: The repair process is straightforward and can typically be performed with the cylinder head still installed on the engine (in most cases). The step-by-step process involves cleaning the damaged hole, tapping the new oversized threads, and screwing in the insert. No specialized training is required, making this kit accessible for both professional workshops and home garage use.
96sets in a carton
Carton size :42*28*23cm
G.W./N.W.15.5/14.5KGS
Qty for 20' container:99360sets
