Chevrolet 1977 light duty truck, Service Manual

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Fig. 6A-22--Checking Valve Spring Tension
If clearance exceeds specifications it will be necessary to
ream valve guides for oversize valves as outlined.
4. Check valve spring tension with Tool J-8056
spring tester (fig. 6A-22).
N O T E : Springs should be compressed to the
specified height and checked against the specifica­
tions chart. Springs should be replaced if not
within 10 lbs. o f the specified load (without
dam pers).
5. Inspect rocker arm studs for w ear or dam age.
Assembly
1. Insert valves in the p roper ports.
2. Set the valve spring shim, valve spring (with
dam per, if used) valve shield and valve cap or rotator in
place (fig. 6A-23).
3. Compress the spring with Tool J-8062.
4. Install oil seal in the lower groove o f the stem,
making sure that the seal is flat and not twisted.
5. Install the valve locks and release the compres­
sor tool, m aking sure that the locks seat properly in the
upp er groove o f the valve stem.
Installation
CAUTiON: The gasket surfaces on both the
head a n d the block m ust be clean o f any
foreign m atter and free o f nicks or heavy
scratches. Cylinder bolt threads in the block
a n d threads on the cylinder head bolt m ust be
cleaned. (Dirt will affect bolt torque.) Do not
use gasket sealer or composition steel asbestos
gasket.
1. Place the gasket in position over the dowel pins
with the bead up.
2. Carefully guide cylinder head into place over
dowel pins and gasket.
3. Coat threads o f cylinder head bolts with sealing
com pound an d install finger tight.
4. Tighten cylinder head bolts a little at a time in
the sequence shown on the torque sequence chart until
the specified torque is reached.
5. Connect ra d ia to r upp er hose and engine ground
strap.
6. Connect tem perature sending unit wires and
install fuel and vacuum lines in clip at water outlet.
7. Fill cooling system.
8. Install m a n ifo ld assem bly as previously
outlined.
9. Install and adjust valve m echanism as previously
outlined.
10. Install an d torque rocker arm cover.
11. Connect AIR pipe (if so equipped).
ROCKER ARM STUDS
Replacement
Rocker arm studs that have d a m a g e d threads o r are
loose in cylinder heads should be replaced with new
studs available in .003" and .013" oversize. Studs m ay be
installed after ream in g the holes as follows:
1. Remove old stud by placing Tool J-5802-A over
the stud, installing n u t and flat w asher and removing
stud by turning nut (fig. 6A-24).
2. Ream hole for oversize stud using Tool J-5715
for .003" oversize or Tool J-6036 for .013" oversize (fig.
6A-25).
•
c a p
S EAL
S H IE LD
* D A M P E R
CAUTION: Do not attem pt to install an
oversize stud without ream ing stu d hole.
3. Coat press-fit area o f stud with hypoid axle