GMC 1990 Light Truck Repair Manual page 375

SUBJECT
Description.................................................................................................................................................................... 6A1- 2
Engine Lubrication....................................................................................................................................................6A1- 2
Disassembly of the Engine......................................................................................................................................... 6A1- 4
Tools and Shop Equipment..................................................................................................................................... 6A1- 4
Accessory Removal..................................................................................................................................................6A1- 4
Cleaning.................................................................................................................................................................... 6A1- 4
Parts Identification....................................................................................................................................................6A1- 4
Draining the Engine..................................................................................................................................................6A1- 4
Intake Manifold Removal......................................................................................................................................... 6A1- 6
Exhaust Manifold Removal..................................................................................................................................... 6A1- 6
Thermostat Housing R em oval............................................................................................................................... 6A1- 6
Water Pump Rem oval............................................................................................................................................. 6A1- 6
Valve Train Component Removal...........................................................................................................................6A1- 9
Cylinder Head Removal........................................................................................................................................... 6A1-10
Crankshaft Pulley Hub Removal.............................................................................................................................6A1-10
Oil Pan Removal........................................................................................................................................................6A1-11
Oil Pump Driveshaft Removal................................................................................................................................. 6A1-11
Oil Pump Removal....................................................................................................................................................6A1-11
Front Cover Removal................................................................................................................................................6A1-11
Piston and Connecting Rod R em oval.................................................................................................................. 6A1-11
Flywheel Removal....................................................................................................................................................6A1-12
Crankshaft Removal..................................................................................................................................................6A1-12
Crankshaft Rear Oil Seal Removal (Without Removing Crankshaft).................................................................6A1-12
Main Bearing Removal (Without Removing the Crankshaft)............................................................................. 6A1-13
Camshaft Removal....................................................................................................................................................6A1-13
Cleaning, Inspection, and Repair............................................................................................................................... 6A1-14
Block...........................................................................................................................................................................6A1-14
Cylinder Bores.......................................................................................................................................................... 6A1-14
Piston and Connecting Rod Assemblies.............................................................................................................. 6A1-15
Piston Selection........................................................................................................................................................6A1-15
Intake and Exhaust Manifold................................................................................................................................... 6A1-15
Camshaft.................................................................................................................................................................... 6A1-16
Camshaft Bearings....................................................................................................................................................6A1-17
Front Cover................................................................................................................................................................ 6A1-17
Water P um p.............................................................................................................................................................. 6A1-18
Oil Pan and Rocker Arm Covers.............................................................................................................................6A1-18
Oil Pump.................................................................................................................................................................... 6A1-18
Valve Train Components............................... ......................................................................................................... 6A1-19
Cylinder Head............................................................................................................................................................ 6A1-19
Thermostat and Housing......................................................................................................................................... 6A1-21
Crankshaft and Bearings......................................................................................................................................... 6A1-21
Assembly of E ngine....................................................................................................................................................6A1-22
Prior to Assem bly....................................................................................................................................................6A1-22
Crankshaft and Main Bearing Installation............................................................................................................ 6A1-22
Crankshaft Rear Oil Seal and Retainer Installation............................................................................................6A1-23
Main Bearing Installation (Without Removing the Crankshaft).........................................................................6A1-24
Camshaft Installation................................................................................................................................................6A1-24
Front Cover Installation........................................................................................................................................... 6A1-24
Crankshaft Pulley Hub Installation.........................................................................................................................6A1-25
Piston and Connecting Rod Installation................................................................................. ............................ 6A1-25
Oil Pump Installation............................................................................................................................................... 6A1-26
SECTION 6A1
2.5 LITER L4 ENGINE
CONTENTS
6A1-1
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