TPD Automotive Ductile Iron Pins, Box of 100

TPD Tapered Threadless Pins offer a cold repair solution for cracked cast metal components like engine blocks and cylinder heads. With a 0.100” small end diameter (smaller than the 0.125” of TPC and 0.200” of TBA pins), these 15/16” long pins are designed for very specific, tight-tolerance applications. Their threadless design allows for easy installation in confined spaces, bridging cracks and providing a strong, durable repair without heat. They are also used to prevent spun bearings in diesel and high-performance engines.

TPD Tapered Threadless Pins are specifically designed for the cold repair of cracks in cast metal components, making them ideal for situations where welding or high-heat processes are undesirable or impossible. Common applications include repairing cracks in cast iron engine blocks, cylinder heads, and other castings. These 15/16” long pins offer a versatile solution for casting repairs, even in the most confined and hard-to-reach locations. The TPD series distinguishes itself with its 0.100” small end diameter, making it suitable for applications requiring a very small pin. This offers a finer, more precise repair option than the TPC (0.125”) or TBA (0.200”) series.

Installation is simple: the tapered threadless pins are inserted into a drilled hole that intersects the crack, effectively bridging the damaged area and preventing further propagation. This cold repair method eliminates the risks of warping, stress, or distortion often associated with high-heat repairs, ensuring a strong and durable fix without compromising the integrity of the casting.

Beyond crack repair, TPD Tapered Threadless Pins are also valuable in high-performance and diesel engine applications for preventing spun bearings. By providing additional alignment and stability to the main bearing shell on the crankshaft journal, these pins prevent the bearing from rotating freely within its housing, minimizing the risk of catastrophic engine damage.

TPD pin hole should be drilled with a #30 sized drill bit.

For a list of all available plugs by size and their associated other tools see the Plug Specifications Catalog in the download link shown above.