TM 5-3895-383-24
Vibration Damper
The force from combustion in the cylinders will cause the
crankshaft to twist. This is called torsional vibration. If the
vibration is too great, the crankshaft will be damaged. The
vibration damper limits the torsional vibrations to an acceptable
amount to prevent damage to the crankshaft.
Rubber Damper (If Equipped)
Rubber Vibration Damper
(1) Crankshaft. (2) Ring. (3) Rubber ring. (4) Hub. (5)
Alignment mats.
The hub (4) and ring (2) are isolated by a rubber ring (3). The
vibration damper has alignment marks (5) on the hub and the
ring. These marks give an indication of the condition of the
vibration damper.
Viscous Damper (If Equipped)
The vibration damper is installed on the front of crankshaft (1).
The damper has a weight (2) in a case (3). The space
between the weight and the case is filled with thick fluid. The
weight moves in the case to limit the torsional vibration.
Cross Section Of Vibration Damper
(1) Crankshaft. (2) Weight. (3) Case.
Camshaft
The camshaft is located in the upper left side of the bock. The
camshaft is driven by gears at the front of the engine. Five
bearings support the camshaft in the four cylinder engine.
Seven bearings are used in the six cylinder engine.
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 valve (either
intake or exhaust). The center lifter assembly moves a push
rod that operates the fuel injector. The camshaft must be in
time with the crankshaft. The relation of the cam lobes to the
crankshaft position cause the valves and fuel injector in each
cylinder to operate at the correct time.
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