Description - GMC 1989 Light Duty Truck Repair Manual

6A5-2 V8 ENGINE
S U B J E C T
Assembly of Engine (Cont.)
Rear Crankshaft Oil Seal and Retainer Installation (5.0 L and 5.7 L Engines).................................................... 6 A 5 -2 9
Camshaft, Timing Chain, and Sprocket Installation.................................................................................................... 6 A 5 -3 0
Front Cover Installation........... ............................................................................................................................................ 6 A 5 -3 0
Torsional Damper Installation.............................................................................................................................................6 A 5 -3 0
Piston and Connecting Rod In s ta lla tio n ........................................................................................................................ 6A5-31
Oil Pump Installation .............................................................................................................................................................6 A 5 -3 2
Oil Pan Installation................................................................................................................................................................. 6 A 5 -3 2
Cylinder Head Installation....................................................................................................................................................6 A 5 -3 3
Valve Train Component Installation................................
Valve Adjustm ent....................................................................................................................................................................6 A 5 -3 4
Intake Manifold Installation................................................................................................................................................. 6 A 5 -3 5
Rocker Arm Cover In s ta lla tio n ...........................................................................................................................................6 A 5 -3 6
Exhaust Manifold In s ta lla tio n .............................................................................................................................................6A 5 -3 6
Water Pump In s ta lla tio n ...................................................................................................................................................... 6 A 5 -3 7
Engine Accessory In s ta lla tio n ...........................................................................................................................................6 A 5 -3 7
Engine Set-Up and T e s tin g ................................................................................................................................................. 6 A 5 -3 7
S p e c ific a tio n s .............................................................................................................................................................................6A5-41
Special T o o ls ...............................................................................................................................................................................6A 5 -4 6
GM V8 engines covered by this section are 90-degree
V8 type, overhead valve, water cooled, with cast iron
block and heads.
The camshaft is supported by five plain type bearings
and is chain driven. Motion from the camshaft is transm it­
ted to the valves by hydraulic lifters, pushrods, and ball-
pivot type rocker arms. The valve guides are integral in
the cylinder head.
The crankshaft is supported by five precision insert type
bearings, with crankshaft thrust taken at the number five
(rear) bearing.
The connecting rods are forged steel, with precision in­
sert type crankpin bearings. The piston pins are a press fit
in the connecting rods.
The pistons are cast aluminum alloy. The piston pins
are a floating fit in the pistons.
The gear type oil pump is driven through an extension
shaft from the distributor driveshaft which is gear driven
from the camshaft. The oil is drawn from the engine oil
pan through a pickup screen and tube. Pressurized oil is
delivered through internal passages to the camshaft and
crankshaft to lubricate the bearings. Lubrication diagrams
are shown in figure 1, 2, and 3.
CONTENTS (CONT.)
........................................................................................... .6 A 5-34

DESCRIPTION

Two basic types of engines, w ith three d iffe re n t
displacements, are covered in this section.
The first type is the " small block" engine, which is
available in 5.0 L (305 cu. in.) and 5.7 L (350 cu. in.)
displacements.
The second type is the 7.4 L (454 cu. in.) engine, which
is sometimes referred to as the " Mark IV" engine.
To determine the displacement of the engine, use the
Vehicle Identification (VIN) of the vehicle the engine was
removed from. Refer to " Specifications" at the end of this
section. If the VIN is not available, the bore and stroke of
the engine involved can be measured and compared
against " Specifications" to determine the engine model.
Refer to G eneral Inform ation (Section OA) in this
manual for further information.
ENGINE IDENTIFICATION
P A G E