BMW N46B20/N43 Crankshaft – OE 11217516040

Overview

A new replacement crankshaft for the N46B20/N43 engine, supplied for BMW applications and cross-referenced to OE 11217516040, 11210142288, 11210142287. It is a direct-fit component for an engine rebuild where the original crank is scored, worn on the journals or has failed a bearing.

Engine application

• Engine code: N46B20/N43
• Listed for: BMW
• OE references: 11217516040, 11210142288, 11210142287, 11217516424, 11210390923, 11217512507

How this part fails

Crankshaft damage is usually a consequence rather than a cause: a spun bearing, a blocked oil way, detonation or a failed oil pump takes the journals out of tolerance. The usual signs are a rhythmic knock that follows engine speed, dropping oil pressure, and metal paste or flakes in the oil filter. Journal scoring beyond the undersize limits means replacement rather than regrinding.

Specifications

Fitment checks before ordering

Crankshafts are not interchangeable on engine capacity alone. Confirm your engine code is N46B20/N43 and that the OE number on your original crankshaft appears in the reference list above before ordering.

Rebuild notes

Before assembly, measure every main and big-end journal for diameter, taper and ovality, and check thrust and runout. Bearings must match the journals as supplied. It is normal practice to renew the rear seal, flush the oil galleries and inspect the oil pump at the same time, then verify clearances with plastigauge during assembly.

What is included

One crankshaft is supplied. Rebuilding an engine also requires bearings, seals and fasteners, which are not part of this listing.

Availability and warranty

The listing does not publish a stock quantity, so availability is confirmed by the supplier at order rather than shown here. The current Alibaba listing quotes delivery by Dec 28. The manufacturer states a 1 year or 10,000 KM, whichever comes first warranty on this listing.