Volvo Penta D2-55, Руководство по ремонту

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Design and function
Camshaft
The camshaft is of conventional design with eight
lobes that operate the pushrods and valves.
Crankshaft
The crankshaft is suspended in five main bearings.
Axial thrust is taken up by separate thrust washers
placed on the rear main bearing. The crankshaft is
statically and dynamically balanced, and has induc-
tion hardened bearing surfaces. The front end of the
crankshaft has a Woodruff key and the rear end has a
flange upon which the flywheel is mounted.
Main and big-end bearings
The main and big-end bearings comprise steelshells
lined with bearing metal. The bearings are precision
made and are ready to be installed.
The thrust washers for the crankshaft axial bearings
are not available in oversize.
Con rods
The con rods are of I -section. The small end is drilled
for gudgeon pin lubrication.
Pistons, piston rings
The pistons are made from aluminum alloy. They are
fitted with three piston rings (chrome plated) – two
compression rings and an oil ring.