Jeep 1996 Grand Cherokee Service Manual page 990

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GENERAL INFORMATION
OIL PUMP PRESSURE . . . . . . . . . . . . . . . . . . . . 53
PISTON AND CONNECTING ROD ASSEMBLY . . 53
VALVES AND VALVE SPRINGS . . . . . . . . . . . . . 53
DESCRIPTION AND OPERATION
ENGINE COMPONENTS . . . . . . . . . . . . . . . . . . 56
ENGINE DESCRIPTION . . . . . . . . . . . . . . . . . . . 53
LUBRICATION SYSTEM . . . . . . . . . . . . . . . . . . . 54
SERVICE PROCEDURES
CRANKSHAFT MAIN BEARINGS . . . . . . . . . . . . 58
CRANKSHAFT . . . . . . . . . . . . . . . . . . . . . . . . . . 59
FITTING CONNECTING ROD BEARINGS . . . . . . 57
FITTING PISTON RINGS . . . . . . . . . . . . . . . . . . 57
FITTING PISTONS . . . . . . . . . . . . . . . . . . . . . . . 57
MEASURING TIMING CHAIN STRETCH . . . . . . . 56
VALVE TIMING . . . . . . . . . . . . . . . . . . . . . . . . . . 56
REMOVAL AND INSTALLATION
CAMSHAFT BEARINGS . . . . . . . . . . . . . . . . . . . 67
CAMSHAFT . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
CRANKSHAFT MAIN BEARINGS . . . . . . . . . . . . 68
CRANKSHAFT REAR OIL SEALS . . . . . . . . . . . . 72
CRANKSHAFT . . . . . . . . . . . . . . . . . . . . . . . . . . 70
CYLINDER HEAD COVER . . . . . . . . . . . . . . . . . 61
CYLINDER HEAD . . . . . . . . . . . . . . . . . . . . . . . . 62
DISTRIBUTOR DRIVE SHAFT BUSHING . . . . . . 68
ENGINE ASSEMBLY . . . . . . . . . . . . . . . . . . . . . . 60
ENGINE CORE OIL AND CAMSHAFT PLUGS . . 74
ENGINE MOUNTS—FRONT . . . . . . . . . . . . . . . . 59
ENGINE MOUNTS—REAR . . . . . . . . . . . . . . . . . 60
GENERAL INFORMATION
VALVES AND VALVE SPRINGS
The valves are arranged in-line and inclined 18°.
The rocker pivot support and the valve guides are
cast integral with the heads.
OIL PUMP PRESSURE
The MINIMUM oil pump pressure is 41.4 kPa (6
psi) at curb idle. The MAXIMUM oil pump pressure
is 207-552 kPa (30-80 psi) at 3,000 RPM or more.
CAUTION: If oil pressure is ZERO at curb idle, DO
NOT run engine at 3,000 RPM.
PISTON AND CONNECTING ROD ASSEMBLY
The pistons are elliptically turned so that the
diameter at the pin boss is less than its diameter
5.2L ENGINE
INDEX
page
FRONT CRANKSHAFT OIL SEAL . . . . . . . . . . . . 71
HYDRAULIC TAPPETS . . . . . . . . . . . . . . . . . . . . 63
OIL PAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
OIL PUMP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
PISTON AND CONNECTING ROD ASSEMBLY . . 70
ROCKER ARMS AND PUSH RODS . . . . . . . . . . 61
TIMING CHAIN COVER . . . . . . . . . . . . . . . . . . . 64
TIMING CHAIN . . . . . . . . . . . . . . . . . . . . . . . . . . 66
VALVE SPRING AND STEM SEAL
REPLACEMENT-IN VEHICLE . . . . . . . . . . . . . 62
VALVES AND VALVE SPRINGS . . . . . . . . . . . . . 63
VIBRATION DAMPER . . . . . . . . . . . . . . . . . . . . . 64
DISASSEMBLY AND ASSEMBLY
CYLINDER BLOCK . . . . . . . . . . . . . . . . . . . . . . . 77
HYDRAULIC TAPPETS . . . . . . . . . . . . . . . . . . . . 75
OIL PUMP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
VALVE SERVICE . . . . . . . . . . . . . . . . . . . . . . . . 75
CLEANING AND INSPECTION
CRANKSHAFT INSPECTION OF JOURNALS . . . 78
CYLINDER BLOCK . . . . . . . . . . . . . . . . . . . . . . . 80
CYLINDER HEADS . . . . . . . . . . . . . . . . . . . . . . . 77
OIL PAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
OIL PUMP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
PISTON AND CONNECTING ROD ASSEMBLY . . 78
SPECIFICATIONS
5.2L ENGINE . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
SPECIAL TOOLS
5.2L ENGINE . . . . . . . . . . . . . . . . . . . . . . . . . . . 85
across the thrust face. This allows for expansion
under normal operating conditions. Under operating
temperatures, expansion forces the pin bosses away
from each other, causing the piston to assume a more
nearly round shape.
All pistons are machined to the same weight,
regardless of size, to maintain piston balance.
The piston pin rotates in the piston only and is
retained by the press interference fit of the piston
pin in the connecting rod.
DESCRIPTION AND OPERATION
ENGINE DESCRIPTION
The 5.2 Liter (318 CID) eight-cylinder engine is a
V-Type lightweight, single cam, overhead valve
engine with hydraulic roller tappets (Fig. 1).
This engine is designed for unleaded fuel.
5.2L ENGINE 9 - 53
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