Caterpillar 4N-0684 Pin

CAT 4N-0684 Pin is a solid dowel pin from Caterpillar, designed for precise alignment of mating parts in CAT equipment. It features a 9.55 mm outer diameter and a length of 0.752 inches (approximately 19.1 mm), providing a compact locating reference for assemblies where exact positioning matters. Marketed by Cat Parts Store as a solid dowel pin, the 4N-0684 designation is consistently referenced in CAT catalogs and aftermarket listings as a flywheel dowel pin. Several supplier references identify it specifically for Caterpillar 3400-series flywheel applications, underscoring its role in aligning the flywheel with the crank hub during assembly and reassembly. As a genuine Cat part, 4N-0684 embodies the standard dimensions used for dowel pins in drive and rotational assemblies, offering a straightforward, repeatable locating feature during service work. This pin is suitable for repairs or rebuilds where a standard dowel pin of these dimensions is required to maintain correct alignment and timing between components, reducing the risk of misalignment that could affect performance.