Specifications

PART 1-1-GENERAL ENGINE SERVICE
1-9
stalled or severe wear has occurred
at the push rod ends, rocker arm, or
valve stem. In this case, it will be
necessary to determine the area of
discrepancy and the incorrect or de-
fective part(s) should be replaced.
If all the valve train components ex-
cept the push rod are within limits,
install a 0.060-inch longer push rod.
2. Rotate the crankshaft until
No. 1 piston is on TDC at the end
of the compression stroke. With
No. 1 piston on TDC, check the fol-
lowing valves:
No. 1 Intake No. 1 Exhaust
No. 3 Intake No. 4 Exhaust
No. 7 Intake No. 5 Exhaust
No. 8 Intake No. 8 Exhaust
3. After these valves have been
checked, position No. 6 piston on
TDC and check the following valves:
No. 2 Intake No. 2 Exhaust
No. 4 Intake No. 3 Exhaust
No. 5 Intake No. 6 Exhaust
No. 6 Intake No. 7 Exhaust
When compressing the valve
spring to remove push rods, be sure
the piston in the individual cylinder
is below TDC to avoid contact be-
tween the valve and the piston.
To replace a push rod, it will
be necessary to remove the valve
rocker arm shaft assembly (Part 1-4).
Upon replacement of a valve
push rod and/or valve rocker arm
shaft assembly, the engine should
not be cranked or rotated until the
hydraulic lifters have had an op-
portunity to leak down to their nor-
mal operating position. The leak-
down rate can be accelerated by
using the tool shown in Fig. 3 on
the valve rocker arm and applying
Detail 1
ADJUSTING SCREW
ECCENTRIC
A1204-A
FIG. 3— Valve Clearance-
Hydraulic Valve Lifters
ADJUSTMENT MARK
FIG. 4—Depressing Valve Rocker
Arm Eccentric
pressure in a direction to collapse
the lifter.
VALVE CLEARANCE—SILENT
VALVE MECHANISM
The silent lash rocker arm is ad-
justed with the engine not operating.
1. Remove the valve rocker arm
cover.
2. Position the No. 1 piston at
TDC at the end of the compression
stroke.
3. Adjust the intake and exhaust
rocker arm for the No. 1 cylinder.
Push the eccentric toward the rocker
arm until the plunger is completely
pushed into its bore in the rocker
arm (Fig. 4). Turn the adjusting
screw in until the eccentric and
plunger are held in the depressed
position (Fig. 4).
4. Slowly turn the adjusting screw
out until the adjustment mark on the
eccentric is centered over the valve
stem (Fig. 5). Torque the lock nut
to specifications to lock the adjust-
ment. The correct position of the
adjustment mark is shown in Fig. 6.
5. Repeat steps 3 and 4 on the
remaining sets of rocker arms. Po-
sition the piston in each cylinder
following the firing order (1-5-3-6-
2-4) on TDC after the compression
stroke and adjust the rocker arms
(intake and exhaust). To position the
individual pistons on TDC in the
firing order, turn the damper ap-
proximately
1
A turn at a time, in
the direction of rotation. This pro-
cedure requires two complete turns
of the crankshaft.
6. After all the rocker arms have
been adjusted, start the engine and
operate it at normal idle speed. Ob-
serve the position of the adjustment
mark on each eccentric. Make minor
adjustments, as necessary, with the
engine idling by turning the adjust-
ing screws in or out as necessary.
7. After making the minor adjust-
ments, stop the engine and install
the valve rocker arm cover.
CAMSHAFT LOBE LIFT
1. Remove the air cleaner and the
valve rocker arm cover(s).
On an engine with mechanical
valve lifters or on the Mileage Maker
Six, slide the rocker arm assembly
serving the camshaft lobe to be
checked to one side. Secure it in
this position. To move the rocker
arm on either end of the shaft, it
will be necessary to remove the re-
taining pin and washers and slide the
rocker arm off the shaft.
On an engine with hydraulic valve
lifters, remove the valve rocker arm
shaft assembly and install a solid
tappet-type push rod in the push rod
bore of the camshaft lobe to be
checked.
2. Make sure the push rod is in
the tappet socket or the lifter push
rod cup. Install a dial indicator in
such a manner as to have the actuat-
ing point of the indicator in the push
rod socket and in the same plane as
the push rod movement (Fig. 7 or
8).
3. Turn the crankshaft damper
slowly in the direction of rotation
until the tappet or lifter is on the
base circle of the camshaft lobe. At
this point, the push rod will be in its
lowest position.
4. Zero the dial indicator. Con-
tinue to rotate the damper slowly
until the push rod is in the fully
raised position.
5. Compare the total lift recorded
on the indicator with specifications.
6. To check the accuracy of the
original indicator reading, continue
to rotate the damper until the indica-
tor reads zero.
7. Remove the dial indicator.
On an engine with mechanical
valve lifters or on the Mileage Maker
A1264-A
FIG. 5—Aligning Eccentric Mark