Lip seals and wear sleeves are used at both
ends of the crankshaft for easy replacement and a
reduction of maintenance cost. Pressure oil is supplied
to all main bearings through drilled holes in the webs of
the cylinder block. The oil then flows through drilled
holes in the crankshaft to provide oil to the connecting
rod bearings. The crankshaft is held in place by five
3512, and nine main bearings on the 3516. A thrust plate
at either side of the center main bearing controls the end
play of the crankshaft.
The engine has a camshaft or camshaft group
for each side of engine, driven at the rear of the engine.
and nine bearings on the 3516 support each camshaft or
camshaft group. The 3512 and 3516 each use two
camshafts per side that are doweled and bolted together
to make a camshaft group. As the camshaft turns, each
lobe moves a lifter assembly. There are three lifter
assemblies for each cylinder.
Each outside lifter
assembly moves a push rod and two valves (either intake
or exhaust). The center lifter assembly moves a push
rod that operates the fuel injector. The camshafts must
be in time with the crankshaft. The relation of the cam
lobes to the crankshaft position cause the valves and fuel
injectors in each cylinder to operate at the correct time.