Technical data

17
9
System components
S85B50 Engine
Basic engine and add-on parts
Upper section of crankcase
The upper section of the crankcase is made
from an aluminium alloy (GK Al-
Si17Cu4Mg T5). The contact surfaces of the
cylinders are machined in accordance with the
Alusil process.
Bedplate
The bedplate consists of an aluminium frame
(G AlSi7Mg0.3 T6) in which the grey cast iron
bearing bridges (GGG 60) are cast. After
casting, the component is subject to stress-
relief annealing for 8 hours at a temperature of
525 °C, it is then quenched in water at 70 °C
and aged for 5 hours at a temperature of
165 °C.
Crankcase
The crankcase comprises the bedplate and
upper section of the crankcase. As already
used on the N42, the seal is provided by a
liquid sealant in a groove that is milled into the
upper section of the crankcase.
It is important that the assembly sequence is
followed precisely in order to avoid stress in
the crankcase when assembling the upper
section and base plate:
1. Position the bedplate diagonally on the
bearing blocks 1 and 6 by means of two
M8x94 screws.
2. Provisionally fasten the bedplate with the
ten M8x94 screws.
3. Tighten the M11x115 bolts to setting
torque
4. Tighten the M11x115 bolts to specified
rotary angle
5. Tighten the M8x94 bolts to setting torque
6. Tighten the M8x94 bolts to specified
torque
7. Tighten the M8x60, M8x35 and M8x25
bolts to the specified torque
Cylinder head
The cylinder head is made from an aluminium
alloy (GK AlSiMgCu0.5 wa).