MITSUBISHI 2310045000 CRANKSHAFT
Product Specifications
| MITSUBISHI | 2310045000 |
The CRANKSHAFT is the engine crankshaft — the primary rotating structural component of the reciprocating internal combustion engine that converts the linear reciprocating motion of the pistons and connecting rods into the continuous rotary torque delivered to the drivetrain. The crankshaft is a precision-forged or cast alloy steel shaft with a series of offset crank throws — each consisting of two crank arms and a crankpin journal — that are angularly phased at equal intervals around the shaft axis according to the cylinder count and firing order to produce evenly spaced power strokes and balanced rotating and reciprocating inertia forces. The crankshaft is supported in the engine block main bearing bores by precision-ground main journals running in replaceable plain shell bearings lubricated by pressurised oil from the main oil gallery; connecting rod big ends connect to the crankpin journals via a second set of plain shell bearings, also oil-pressure-lubricated through drillings from the main journals. Counterweights forged integrally with the crank arms offset the mass of the crank throws and the lower connecting rod to cancel primary and secondary rotational imbalance forces at operating speed, minimising vibration transmitted to the engine mounts and body. The crankshaft nose carries the timing sprocket or pulley, the crankshaft position sensor reluctor ring, and the vibration damper pulley; the flywheel end carries the flywheel flange and the pilot bearing bore for the transmission input shaft.
This unit — MITSUBISHI 2310045000 — is manufactured to OEM-equivalent specifications: main journal and crankpin journal diameter and surface finish (Ra ≤0.4 μm), journal fillet radius geometry, main bearing bore centreline spacing, crank throw offset and angular phasing, oil drilling positions and diameters, reluctor ring tooth count and reference gap position, flywheel bolt flange bolt circle, front nose keyway and thread dimensions, and dynamic balance class are matched to the original part. Supplied individually as a complete crankshaft assembly. Available wholesale from 72.56 USD, MOQ 5 pcs, production lead time 15-40 days.
Crankshafts fail through main and crankpin journal bearing surface scoring and spalling from oil starvation — the most common failure mode, caused by inadequate oil pressure from a failed pump, blocked oil passages, or severely depleted oil level; through fatigue cracking at the high-stress fillet radius between the journal and the crank arm from detonation-induced overloads on turbocharged engines; and through torsional fatigue fracture of the shaft body from sustained operation with a failed vibration damper that allows torsional resonance to build to destructive amplitude. Journal surface damage that has progressed beyond the serviceable limit for grinding and fitting undersize bearings requires crankshaft replacement — a scored or cracked crankshaft cannot be reliably repaired to the surface finish and dimensional accuracy required for hydrodynamic bearing operation.
- Measure all engine block main bearing bore diameters before installing the new crankshaft — a block with worn or out-of-round main bearing bores cannot provide the correct housing bore diameter for the new bearing shells; each bore must be within the OEM tolerance at two perpendicular orientations; bores outside tolerance require line boring before the new crankshaft is installed; never install a new crankshaft into a block with unmeasured or out-of-tolerance bearing bores.
- Measure the new crankshaft's main and crankpin journal diameters and surface finish before installation — confirm each journal diameter is within the OEM standard or specified undersize tolerance; inspect the surface finish at 90-degree intervals around each journal under magnification for any machining marks, pitting, or handling damage; a journal with surface irregularities below Ra 0.4 μm will destroy the new bearing shells within a short operating period.
- Verify bearing clearances with Plastigage on all main journals before final assembly — place a strip of Plastigage across each journal, torque the main bearing cap to specification, remove the cap, and measure the crushed Plastigage width against the reference card; the clearance on each journal must fall within the OEM specification — typically 0.020–0.060 mm; clearances outside this range require bearing shell selection by grade or journal regrinding; never assemble the engine with unmeasured bearing clearances.
- Lubricate all bearing shells, journal surfaces, and thrust washers with fresh engine oil or assembly lube immediately before installation — the crankshaft's journals are in boundary lubrication for the first seconds of operation before the oil pressure circuit fills; a dry bearing surface during the first crankshaft revolution produces immediate scoring that destroys the new journal surface; coat every bearing surface generously with clean engine oil of the correct specification before the crankshaft is lowered into the block.
- Torque all main bearing cap bolts in the OEM sequence and in the specified number of passes — main bearing caps on modern engines use torque-to-yield stretch bolts that must be replaced at every assembly; the torque sequence — typically from centre caps outward — and the multi-pass tightening procedure are critical for correct bearing bore geometry; a cap tightened out of sequence or in a single pass distorts the bore and produces bearing shell fretting from the first revolution.
- Install the new CRANKSHAFT (MITSUBISHI 2310045000), complete all engine assembly with new gaskets, seals, and oil filter, prime the oil circuit by cranking without the ignition system enabled until oil pressure is confirmed on a gauge, start the engine and hold at 2,000 RPM for 5 minutes while monitoring oil pressure continuously, then perform the OEM specified run-in procedure before subjecting the engine to full load; do not exceed 3,000 RPM or apply full throttle during the first 500 km of operation.
| Part | Reason for Combined Replacement |
|---|---|
| Main and Connecting Rod Bearing Shell Set Standard or undersize — matched to journal diameter | New bearing shells must always be fitted with a new or reground crankshaft — reusing old shells against a new crankshaft immediately introduces the old shell's worn surface profile and embedded abrasive particles to the new journal surface. Select shells by grade to achieve the OEM clearance specification confirmed by Plastigage measurement; shells of the correct grade installed to the measured clearance are the most critical single factor in crankshaft and bearing longevity. |
| Engine Oil Pump OEM ref. varies by engine | Crankshaft bearing failure caused by inadequate oil pressure from a worn or failed oil pump must be addressed simultaneously with the crankshaft — fitting a new crankshaft with the same failed pump reproduces the oil starvation condition from the first startup. With the engine fully disassembled for crankshaft replacement, the oil pump is fully accessible; always test the old pump's pressure output against the OEM specification and replace it if it is below specification or if its service life is unknown. |
| Engine Rebuild Gasket Set Complete set including head gasket, seals, and O-rings | Crankshaft replacement requires complete engine disassembly, during which every gasket and seal in the engine is disturbed; all must be renewed at reassembly — reusing any gasket or seal from a disassembled engine produces a leak at that joint within a short operating period from the permanent compression set that the old gasket or seal has taken. A complete engine gasket set ensures every sealing interface is renewed simultaneously in a single assembly operation. |