TPA Automotive Ductile Iron Pins, Box of 100

TBA Tapered Threadless Pins offer a cold repair solution for cracked cast metal components like engine blocks and cylinder heads. With a 0.200” small end diameter (compared to the 0.125” of TPC pins), these 15/16” long pins are designed for specific 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.

TBA 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 key difference between the TBA and TPC series is the small end diameter: TBA pins have a 0.200” diameter, while TPC pins are 0.125”. This makes TBA pins suitable for applications requiring a slightly larger pin.

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, TBA 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.

Other tools used with these pins: 407-5102-00 TPA 11/64” HSS Drill Bit 407-5202-35 HSS Tapered Reamer

See our Plug Specification Chart for other available sizes (linked above).