Engine Crankshaft Kit

What Is an Engine Crankshaft Kit?

The crankshaft is one of the most fundamental components inside any internal combustion engine. It converts the linear up-and-down motion of the pistons into the rotational force that ultimately drives your wheels. Over time — or after a significant engine failure — the crankshaft and its associated bearings can wear beyond acceptable tolerances, leading to reduced oil pressure, increased engine noise, vibration, and eventually catastrophic engine damage if left unaddressed.

An engine crankshaft kit takes the guesswork out of sourcing individual components for a bottom-end rebuild. Rather than hunting down a crankshaft, rod bearings, and main bearings separately, a crankshaft kit bundles all the essential components together under a single part number. This not only simplifies the ordering process but also ensures that every included piece is properly matched to work together — a critical consideration when rebuilding to tight tolerances.

What's Typically Included in a Crankshaft Kit?

• Remanufactured or new crankshaft – machined to OEM specifications
• Rod bearings – sized to match the crankshaft's rod journals
• Main bearings – sized to match the main journals
• Thrust washers (where applicable) – to control crankshaft end-play

The rod and main journals on a remanufactured crankshaft are often ground to a specific oversize to clean up worn or scored surfaces. The bearings included in the kit are matched to that oversize, so everything fits correctly right out of the box. Always verify the journal sizing against your block and connecting rods before final assembly.

When Do You Need a Crankshaft Kit?

Crankshaft kits are most commonly used during a full engine overhaul or rebuild, but they are also called for when diagnosing a spun bearing, low oil pressure caused by excessive bearing clearance, or visible scoring on the crank journals. Any time a short block is being disassembled for inspection, it is worth measuring journal diameters and checking for out-of-round conditions to determine whether a fresh crankshaft kit is warranted.

Top Brands in Engine Crankshaft Kits

Enginetech is one of the most widely trusted names in engine rebuild parts, offering an extensive catalog of crankshaft kits for domestic and import passenger vehicles and light trucks. Enginetech's crankshaft kits include a remanufactured crankshaft along with matching oversized rod and main bearings, with each casting handled individually and machined to OE specifications. The convenience of a single part number covering all required components makes Enginetech a go-to choice for professional engine builders and DIY rebuilders alike.

Athena brings its powersports and motorsport expertise to the crankshaft kit segment, catering to motorcycles, scooters, and off-road machines. Athena's crankshaft kits are engineered to match the original engine configuration for straightforward installation, with bearings sourced from premium manufacturers and all components selected to perform under high thermal and mechanical stress.