Fasteners and hardware components are fundamental to the structural integrity of Cummins engines. From cylinder head bolts that maintain correct clamping loads to retaining rings and dowel pins that keep rotating assemblies properly aligned, each fastener is specified to meet precise torque requirements, material grades, and dimensional tolerances. Engine vibration, thermal cycling, and high clamping forces mean that reusing stretched or damaged fasteners can lead to joint failure, oil or coolant leaks, and component damage. Many Cummins fasteners — particularly cylinder head capscrews, connecting rod bolts, and main bearing cap bolts — are torque-to-yield and must be replaced during overhaul rather than reused.
AMS Parts supplies a wide range of fasteners & hardware components for Cummins engines used in power generation, marine, and industrial applications. Browse a selection of available parts below, or contact us for specific requirements.
Below is a selection of fasteners & hardware parts we supply. Use the search bar above to find a specific part number, or request a quote. You can also reach us directly at [email protected] or +44 7776 800169.
Many Cummins cylinder head capscrews are torque-to-yield (TTY), meaning they are designed to stretch permanently during installation. Reusing TTY bolts risks insufficient clamping force, which can lead to head gasket failure. Always check the service manual for the specific engine model to confirm whether bolts are reusable.
Cummins fasteners are specified by material grade, thread pitch, length, and surface treatment. A bolt that looks similar but has a different grade or length can fail under load or cause incorrect clamping. Using the OEM part number ensures the fastener meets the engineering specification for that joint.
Torque values are specific to each fastener application and engine model. They are published in the relevant Cummins service manual. Using incorrect torque values — either too high or too low — can cause joint failure, gasket leaks, or thread damage.
