TM 9-2320-266-34
c. Install a dial indicator so the plunger contacts the valve
(2) Place a torque wrench and socket over the cam-
spring retainer as nearly perpendicular as possible.
shaft sprocket attaching bolt and apply torque in the direc-
tion of the crankshaft rotation to take up the slack; apply
d. Allow the spring load to bleed the tappet down, giving
30 ft-lbs if the cylinder heads are installed, or 15 ft-lbs if the
in effect a solid tappet. Zero the indicator.
cylinder heads are removed. After torque is applied to the
e. Rotate the crankshaft clockwise until the valve has
camshaft sprocket bolt, do not permit the crankshaft to
lifted 0.010 inch. The timing of the crankshaft pulley should
move. It may be necessary to block the crankshaft to pre-
now read from 10 degrees before "O" (TDC) to 2 degrees
vent rotation.
after "O." Remove the spacer.
(3) Holding a scale with the dimensional reading even
with the edge of a chain link, apply torque in the reverse
direction (30 ft-lbs with cylinder heads installed or 15 ft-lbs
Do not turn the crankshaft any further
with cylinder heads removed). Note the amount of chain
clockwise, as the valve spring might bet.
movement (figure 3-8).
tom and damage the tappet.
f. If the reading is not within specified limits:
(1) Check the sprocket index marks.
(2) Inspect the timing chain for wear
(3) Check the accuracy of the "O" TDC mark on the
timing indicator.
3-9. Timing Chain Cover, Oil Seal, and Chain.
a. Removing the Cover.
(1) Disconnect the negative (ground) cable at the
battery.
(2) Drain the cooling system and remove the radiator,
fan belt, and water pump assembly.
(3) Remove the pulley from the vibration damper.
Remove the bolt and washer securing the vibration damper
on the crankshaft.
Figure 3-8. Measuring Timing Chain Stretch.
(4) Install a puller and remove the vibration damper
(4) Install a new timing chain, if its movement exceeds
from the end of the crankshaft (figure 3-7).
one-eighth inch.
c. Replacing Timing Chain and Sprockets. Replace the
timing chain, and the camshaft and crankshaft sprockets as
a set if any one of the three is bad.
(1) Remove the timing chain cover (a, above).
(2) Remove the cup washer that attaches the sprocket
to the camshaft. Remove the fuel pump eccentric. Remove
the timing chain and the crankshaft and camshaft sprockets
as an assembly.
(3) To install a new chain, remove the distributor and
oil pump distributor drive gear. Use tool C-3509 to avoid
contact between the camshaft and the welch plug in the rear
Figure 3-7. Removing Vibration Damper Assembly.
of the engine block.
(5) Remove the fuel lines and fuel pump.
(4) Locate the tool against the rear side of the cam
gear and attach the tool with the distributor retainer plate
(6) Loosen the oil pan bolts and remove the front bolt
bolt, as shown in figure 3-9. (The figure shows accessories
at each side.
removed, for clarity).
(7) Remove the chain case cover and gasket. Use ex-
treme caution to avoid damaging the oil pan gasket.
(5) Place the camshaft and crankshaft sprockets on
the bench with the timing marks on the centerline through
b. Measuring Timing Chain for Stretch.
both bores.
(2) Place a scale next to the timing chain so that any
(6) Place the timing chain around both sprockets.
movement of the chain may be measured.
3-5
