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8-12
(I terminal) and the red
and blue lead
(5 terminal) at the starter relay.
Install an auxiliary starter switch
between the battery and S terminals
of the starter relay. Crank the engine
with the ignition switch off until
the No.
1
piston
is
on T.D.C. after
the compression stroke.
By using procedure in Step
3,
check the following valves:
No.
1
intake.
No.
3
exhaust.
No.
1
exhaust.
No. 4 intake.
No. 2 intake.
No.
5
exhaust.
2.
Now rotate the crankshaft until
the No. 6 piston is on T.D.C. after
the compression
stroke
(1 revolution
of the crankshaft). By using the
procedure in
step
3, check the
following valves:
No. 2 exhaust.
No. 5 intake.
No. 3 intake.
No. 6 intake.
No. 4 exhaust.
No. 6 exhaust.
3. Using
tool
6513AG,
apply
pressure on
the
push
rod
end of the
rocker arm
(Fig.
12) to slowly bleed
down the valve lifter until the plunger
is completely bottomed. Hold the
lifter in this position and check the
available clearance between the rock-
er arm and the valve stem tip
with
a feeler gauge.
If clearance is not within specifica-
tions, tum the adjusting screw clock-
wise to decrease or counter-clock-
wise to
increase,
the clearance.
Normally, one turn of the adjusting
screw
will
alter the clearancr by
0.075 inch at the valve stem tip.
VALVE CLEARANCE-
HYDRAUUC VALVE LIFTERS,
V-8 Engines
The cylinders are numbered from
front to rear-right bank, 1-2-3-4;
left bank, 5-6-7-8.
The valve arrangement on the
left
bank is
E-1-E-1-E-1-E-1 and on the
right bank is
1-E-1-E-1-E-1-E.
A
0.060-inch
shorter
push rod
or a
0.060-inch
longer push
rod
are avail-
able for service to provide a
means
of
compensating for
dimensional
changes in
the valve
mechanism.
Refer
to the
Master Parts List for
the
pertinent color
code.
Valve stem
to
valve
rocker
arm
clearance
should be within specifica-
tions with the
hydraulic lifter com-
pletely
collapsed.
Repeated
valve
re-
conditioning operations (valve and/or
valve seat refacing)
will decrease the
clearance to
the
point
that if not
compensated for,
the
hydraulic valve
lifter will cease to function and
the
valve will
be
held
open.
To
determine
whether a shorter or
a
longer push rod
is necessary,
make
the
following check
:
GROUP 8-
ENGINE
1.
Disconnect the brown/red lead
(I terminal) and the red and blue lead
(S terminal) at the starter relay. Install
an
auxiliary
starter
switch between
the battery and S terminals of the
Starter relay. Crank the engine with
the ignitions switch
0
FF until the
No.
I piston is on TDC after the
compression stroke.
2. With
the
crankshaft
in
the
positions designated in Steps 3, 4 and
5
position the hydraulic lifter com-
pressor tool on the rocker arm. Slow-
ly apply pressure to bleed down the
hydraulic lifter until the plunger is
completely bottomed (Fig. 14 ). Hold
the lifter in this position and check
the available clearance between the
rocker arm and the valve stem tip
with
a
feeler gauge. The feeler gauge
width must not exceed 3/8-inch.
If the clearance is less than specifi-
cations, install an undersize push rod
.
If the clearance is greater than speci-
fications, install an oversize push rod.
3. With the No. I piston on TDC
at the end of the compression stroke,
POSITION A in Fig. 13, check the
following valves:
No. 1 Intake
No. 1 Exhaust
No.4 Intake
No. 3 Exhaust
No.8 Intake
No.7 Exhaust
4. Rotate the crankshaft to POSI-
TION 8 in Fig. 13 and check the fol-
lowing valves:
No. 3 Intake
No. 2 Exhaust
No.7 Intake
No. 6 Exhaust
5. Rotate the crankshaft to POSI-
TION C in Fig. 13 and check the fol-
lowiniZ valves:
No. 21ntake
No.4 Exhaust
No. 5 Intake
No. 5 Exhaust
No.6 Intake
No.8 Exhaust
The rocker arm, bolt, fulcrum seat
and rocker arm eliminates the neces-
sity of adjusting.
FIG. 12 -Yalft
ca....c.
Check
-
6 CYL
FIG. 14
Valve Clearance
Check-V-8
he valve clearance. However, to ob-
tain the
specified valve
lash. it is im-
portant that
all
valve components
be
in a serviceable condition
and
in-
stalled and torqued properly.
With
the
crankshaft
in
the
positions designated in
steps
2, 3 and
~.
·.
4 remove the fulcrum seat and rocker
·•
arm. Inspect them for wear. See Fig.
15.
VALVE ROCKER ARM
ASSEMBLY
If the pad at the valve end of
::
.
...
''·
POSITION A - No.
1
at
TDC
ot
end of compression str'oke.
-:
POSITION 8
-Rotate the crankshaft
180 degrees
(one
hoH
,.
revolution) clockwise from
POSITION A.
POSITION C
-
Rotate
the cronkshoh 270
degrees
(three
quarter revolut ion) clockwise from
POSITION B.
W1th No.
1
at TDC at end of
compreu•o~
stroke
make o
chalk mark
ot points Band C opproxtmotely
90
degrees apart.
,.
.
FIG. 13 - Position of Crankshaft for Checking and
Adjusting Valve Clearance
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