Intake Manifold; Exhaust Manifold; Cylinder Head - GMC T Series 1994 Repair Manual

CHECKING OIL HOLE ALIGNMENT W ITH BRASS
ROD. MAKE AS SHOWN USING 3/32" ROD
ABOUT 762MM (30") LONG.
1 90° BEND
Figure 34 - Checking Camshaft Bearing Oil Hole
Alignment
0
Remove or Disconnect
1. Camshaft, refer to " Camshaft" in this section.
2. Camshaft bearings.
- Select the proper pilot, nut and thrust washer.
- Assemble J 33049. Make sure the puller nut
engages a sufficient number of threads.
- Pull out bearings, refer to Figure 33.
Important
Camshaft bearings must not be reused once they
have been removed.
-M- Install or Connect
1. Camshaft bearings.
- Select front, rear and intermediate camshaft
bearings.
- Select the proper pilot, nut and thrust washer.
- Assemble J 33049.
- Place bearing onto J 33049 and index the oil
hole(s) of the bearing with the oil passage(s) in
the cylinder block. Pull bearing into place.
NOTICE:
Proper alignment of the oil holes is
critical. Restriction of the oil flow will cause
severe engine damage.
Camshaft plug.
- Apply GM P/N 1052914 sealer (or equivalent)
to the plug before installing.
L*
Inspect
With a piece of 3/32 inch brass rod with a 90°
bend at the end, probe the bearing oil holes and
verify that they are properly aligned, refer to
Figure 34.
Mating surfaces on intake manifold and cylinder
head.
EGR passage of excessive carbon deposits.
Manifold for cracks, broken flanges and gasket
surface damage.
] Clean
Mating surfaces at cylinder head and exhaust
J10278-6A-W-EDS
manifold.
Manifold for cracks, broken flanges and gasket
surface damage.
Alignment of exhaust manifold mating surfaces.
Use a straight edge and feeler gage. If the flanges
or mating surfaces do not align, the manifold is
warped and should be replaced.
• Cylinder head. Rocker arm studs that have
damaged threads should be replaced. If the threads
in the head are damaged or stripped, the head can
be re-tapped, and a helical type insert added, refer
to " Thread Repair" in this section. If such an
insert is not available, the head should be
replaced.
• Gasket surfaces on both the head and the block
must be clean of foreign matter and free of nicks
or heavy scratches. Cylinder bolt threads in the
block and threads on the cylinder head bolts must
be clean. (Dirt will affect bolt torque.)
VALVE AND SPRING DISASSEMBLY
m
2
.
3.

INTAKE MANIFOLD

Clean
Inspect

EXHAUST MANIFOLD

Inspect

CYLINDER HEAD

Inspect
Tool Required:
J 8062 Valve Spring Compressor
Disassemble
Important
• Be sure that valve train components are kept
together and identified so that they can be
installed in their original location and with the
same mating surfaces as when removed.
Compress valve springs using J 8062 and remove
valve locks.
Release J 8062 and remove.
Remove spring cap, spring, seal, and inlet spring
washers.