of a new bushing (installed is 1.0015 inch-1.0027 inch,
(2) The accessory drive is properly timed to
and the O.D. of lower shaft at the bushing location is
the engine when the keyway (fig. 67) in
.999 inch-1.000 inch. If bushing is worn it may be
the lower shaft is to the top and in line
replaced as follows:
with an imaginary centerline between the
lower shaft and slightly to the left of the
(a) Remove lower shaft oil seal (27)
center of the drive adapter when the
from the cover.
accessory drive assembly is secured in
(b) Remove bushing retaining snap ring
position on the timing gear housing.
(26) and drive old bushing out
toward snap ring end of the bore.
Note. When starting the accessory
(c) Using a suitable installing tool, drive
drive into the timing gear housing, it
or press a new bushing into position
in cover until it is tight against the
will be necessary to position the
shoulder in the bore. Make certain
keyway slightly left of the centerline.
oil hole in bushing is to the bottom
This is to compensate for the gear
angle which causes the lower shaft to
retaining snap ring.
rotate clockwise as the accessory drive
The bushing is the
is moved forward into position.
precision type and does not
This is a trial and error method and must
be repeated until the keyway in the lower
(16) Install a new oil seal in the drive adapter
shaft is to the top and on the imaginary
(24) and a new oil seal in the lower bore
centerline between the lower shaft and the
of the cover with the sealing lip of the seal
overspeed governor drive adapter as
directed toward the inside of the cover.
positioned as described in the preceding
Note. Coat the O.D. of the seals with
a small amount of sealant.
(3) Install the woodruff key in the accessory
(17) Using a new gasket, attach the cover to
drive lower shaft and install the fuel
injection pump drive coupling hub on the
Tighten capscrews securely.
shaft: Secure the coupling to the shaft
(18) Using a new gasket, install the drive
with the clamping capscrew and
adapter, drive cover nut, and gasket.
f. Accessory Drive Installation. The accessory
(4) Install and time the fuel injection pump
drive must be timed to the engine so that the keyway
(refer to TM 5-6115-400-12).
is properly positioned for installation and timing
of the fuel injection pump. Install the accessory drive on
47. Crankshaft Pulley and Damper
the engine as follows:
. The vibration damper (fig. 68) consists
(1) Use barring tool to rotate engine until the
of two identical vibration dampers which are attached to
#1 piston is on its compression stroke and
the crankshaft pulley. Each consists of a metal ring
the engine flywheel timing pointer
enclosed in a fluid tight outer case but separated from
registers 34 degrees BTDC for start of
contact with the, case by a thin wall of viscous liquid that
fuel injection into the #1 cylinder.
tends to dampen the torsional vibrations of the
crankshaft. This damper should give no trouble, but it
must be given proper care. It must not be dropped or
struck with a hammer or similar object. Doing so can
upset its balance. For the dampers to function properly,
they are aligned with the crankshaft pulley by dowel pins
and fastened securely to the pulley with capscrews and