Crankshaft - BMW S58 Owner's Handbook Manual

S58￿Engine
4.￿Engine￿Mechanical
If￿there￿is￿a￿complaint￿about￿higher￿oil￿consumption￿and￿at￿the￿same￿time￿an￿exhaust￿turbocharger
fouled￿with￿oil￿is￿diagnosed,￿then￿it￿cannot￿be￿immediately￿concluded￿that￿the￿exhaust￿turbocharger
is￿faulty.￿If￿the￿fouling￿is￿already￿present￿after￿the￿introduction￿of￿the￿blow-by￿gases,￿then￿the￿entire
engine￿must￿be￿checked￿for￿leaks.￿The￿cause￿of￿an￿excessive￿blow-by￿gas￿flow￿rate￿may￿be￿faulty
gaskets￿or￿crankshaft￿seals.￿Leaking￿crankshaft￿seals￿may￿generate￿oil￿consumption￿of￿up￿to￿3
liters/1000￿km￿(620￿miles).
4.1.6.￿Engine￿cover
The￿engine￿cover￿was￿adapted￿to￿the￿S58￿engine.￿The￿engine￿cover￿is￿also￿the￿intake￿silencer￿of￿the
S58￿engine.
S58￿engine,￿engine￿cover
4.2.￿Crankshaft
4.2.1.￿Crankshaft￿with￿bearings

Crankshaft

The￿crankshaft￿is￿an￿optimized-weight￿design￿and￿has￿been￿adapted￿to￿the￿high-revving
characteristics￿and￿greater￿power￿output￿of￿the￿S58￿engine.￿Thus￿the￿crankshaft￿of￿the￿S58￿engine
weighs￿approx.￿21.2 kg￿(47￿lbs).￿The￿crankshaft￿is￿also￿called￿a￿lightweight￿construction￿crankshaft.
The￿crankshaft￿is￿made￿from￿a￿steel￿alloy￿42CrMoS4￿Mod￿and￿is￿then￿nitrocarbonized￿in￿the￿gas.
The￿timing￿chain￿and￿oil￿pump￿are￿connected￿by￿gears.

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