Cylinder Head-Exploded View; Valve Location; Valve Seal Identification; Reconditioning Valves - Pontiac TRANS AM 1977 Service Manual

6A4- 1 2
1977 PONTIAC SERVICE MANUAL
Fig. 6A4-22 Cylinder Head
-
Exploded View
4. Remove oil seals from valve stems.
5. Remove valves. Keep valves separated so they can be
installed in their original locations. (Fig. 6A4-23)
INTAKE VALVES
Fig. 6A4-23 Valve Location
Installation
1. Install valves in their respective guides.
VALVE SEAL IDENTIFICATION
Intake
Std.
-
.005" O.S.
-
Gray Colored
.OIOn
-
.013" 0.S.- Orange Colored
Exhaust
Std.
-
.005" O.S.
-
Ivory Colored
.010"
-
.013" 0.S.- Blue Colored
2. Install new oil seals over valve stem, using Tool BT-
6804 (Fig. 6A4-24).
PUSH IHE VALVE SEAL
SQUARELY ONTO THE
VALVE STEM UNTIL THE
Fig. 6A4-24 Valve Seal Location
Position seals down as far as possible on valve stem. The
seals will correctly position themselves when the engine is
started.
NOTE: Inspect seal for cracks after installation.
3. Position valve springs over valve stems.
4. Install valve rotators then compress springs with a tool
such as BT-6413-2 and install valve stem keys.
5. Check valve springs and keys to be sure they are
properly seated.
Installation
Head gaskets are a special composition gasket that must
be used WITHOUT a sealer. These gaskets are to be installed
with the contrasting color stripe facing "up" (Fig. 6A4-25).
1. Clean and dip cylinder head bolts in engine oil, torque
bolts to 100 ft. lbs. in sequence shown, then re-torque the head
bolts to 130 ft. lbs. (Fig. 6A4-26).
2. Complete installation by reversing removal procedure.
Reconditioning Valves
When reconditioning valves and valve seats, clean
carbon from cylinder heads and valves using care not to gouge
or scratch machined surfaces. A soft wire brush is suitable
for this purpose. Whenever valves are replaced or new valves
installed, the valve seats must be reconditioned. (Fig. 6A3-27)
Narrow the valve seats to the specified width.
NOTE: This operation is done by grinding with a 30"
stone to lower the seat and a 60' stone to raise the seat.
See "engine specification" chart for valve seat width.
NOTE: Exhaust valve seats are induction hardened and
must be ground, not cut.
If valve guide bores are worn excessively, they can be
reamed oversize. This will require replacement of the valves
with oversize valves (stems). The guide bores should be
reamed before grinding the valve seats. Valve clearance in
guide bore should be 0015" to .0032" (exhaust) or .002" to
.0027" for the intake valve.