BMW S58, Руководство пользователя

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S58�Engine
4.�Engine�Mechanical
24
S58�engine,�crankshaft
Index Explanation
1 Main�bearing
2 Drive�for�oil�pump�and�valve�gear
3 Connecting�rod�bearing
Crankshaft�main�bearing
The�crankshaft�main�bearings�are�adapted�to�the�S58�engine.�Adaptations�were�necessary�in�order
to�satisfy�the�higher�demands�of�the�high-revving�design.�The�bearings�are�a�lead-free�design.�The
material�combination�for�the�lower�bearing�shells�takes�the�form�of�a�Federal�Mogul�G488.�For�the
upper�bearing�shells�a�Federal�Mogul�G490�is�used.�The�thrust�bearing�is�located�at�the�4th�bearing
position.
When�replacing�the�crankshaft�main�bearings,�the�bearing�shell�classification�must�be�taken�into
account.�The�precise�procedure�for�replacing�the�crankshaft�main�bearing�shells�can�be�found�in�the
up-to-date�information�in�the�BMW�workshop�system�ISTA.
4.2.2.�Connecting�rod�with�bearing
The�forged�connecting�rod�of�the�S58�engine�has�a�nominal�length�of�151.1 mm.�The�connecting
rod�is�a�carry-over�part�from�the�S63B44T4�engine.�As�with�other�BMW�engines,�the�small�end�has�a
profiled�bore.�The�force�acting�from�the�piston�via�the�wrist�pin�is�optimally�distributed�to�the�bushing
surface�by�this�shaped�bore�and�the�edge�load.