5.7L Engine - Service Information: Overview Jeep Commander I

The 5.7L engine (345 CID) eight-cylinder engine is a 90° V-Type lightweight, deep skirt cast iron block, aluminum heads, single cam, overhead valve engine with hydraulic roller tappets. The heads incorporate splayed valves with a hemispherical style combustion chamber and dual spark plugs. The cylinders are numbered from front to rear; 1, 3, 5, 7 on the left bank and 2, 4, 6, 8 on the right bank. The firing order is 1-8-4-3-6-5-7-2.

ENGINE DIAGNOSIS - INTRODUCTION

Engine diagnosis is helpful in determining the causes of malfunctions not detected and remedied by routine maintenance.

These malfunctions may be classified as either performance (e.g, engine idles rough and stalls) or mechanical (e.g, a strange noise).

See ENGINE DIAGNOSIS - PERFORMANCE and ENGINE DIAGNOSIS - MECHANICAL for possible causes and corrections of malfunctions.

Additional tests and diagnostic procedures may be necessary for specific engine malfunctions that can not be isolated with the Service Diagnosis charts. Information concerning additional tests and diagnosis is provided within the following diagnosis

1. Cylinder Compression Pressure Test. See «CYLINDER COMPRESSION PRESSURE»(ref-288237-S10990776372008062000000) .
2. Cylinder Combustion Pressure Leakage Test. See «CYLINDER COMBUSTION PRESSURE LEAKAGE»(ref-288237-S41069679712008062000000) .
3. Engine Cylinder Head Gasket Failure Diagnosis. See «CYLINDER HEAD GASKET FAILURE»(ref-288237-S36762493612008062000000) .
4. Intake Manifold Leakage Diagnosis. See «INTAKE MANIFOLD LEAKAGE»(ref-288237-S38466562852008062000000) .

DESCRIPTION VALVE GUIDE SEAL

The valve guide seals are made of rubber and incorporate an integral steel valve spring seat. The integral garter spring maintains consistent lubrication control to the valve stems.

Scheme 207

Scheme 208

Scheme 209

Scheme 210

1. Disconnect negative battery cable.
2. Remove air cleaner assembly.
3. Remove air intake resonator.
4. Remove ignition coil connector (1).
5. Remove ignition coils (2).
6. Remove one spark plug.
7. Remove cylinder head cover (1) using the sequence shown in illustration. (See «REMOVAL»(ref-288237-S17377271092008062000000) ). 1 - PUSH ROD RETAINER FASTENER 2 - PUSH ROD RETAINER 9070 CAUTION: The piston must be at TDC, and both valves closed on the cylinder to be serviced. NOTE: If removing intake valve spring, install push rod retaining plate 9070, (1), to retain the intake push rods (2).
8. Remove exhaust/intake rocker arm shafts using the sequence shown in illustration. 1 - ROCKER ARM SHAFT 9065
9. Install rocker arm shaft 9065 (1). 1 - VALVE SPRING COMPRESSOR TOOL 9065 1 - EXHAUST ADAPTER 9065 2 - ADAPTER PIN 3 - VALVE SPRING COMPRESSOR 9065
10. Install spring compressor 9065 (1,3,) and exhaust adapter arm (1) if needed. NOTE: All valve springs and seals are removed in the same manner. 1 - AIR HOSE 2 - DUMMY SHAFT 3 - VALVE SPRING COMPRESSOR 9065
11. Insert air hose (1) into spark plug hole and charge cylinder with air. NOTE: Tap the top of the valve spring retainer to loosen the spring retainers locks.
12. Compress valve spring with valve spring compressor 9065 (3) and remove valve retainer locks.
13. Release spring compressor (3) and remove valve spring. NOTE: The valve springs are interchangeable between intake and exhaust.
14. Remove valve seal.

Scheme 211

1. Install valve seal.
2. Install valve spring.
3. Using special tool# 9065 (1,3,), compress valve spring and install valve spring retainer and locks. 1 - AIR HOSE 2 - DUMMY SHAFT 3 - VALVE SPRING COMPRESSOR 9065
4. Release air charge in cylinder (1).
5. Remove spring compressor tool # 9065 (3). CAUTION: Verify that the pushrods are fully seated into lifter and rocker arm. Recheck after rocker arm shaft has been torqued to specification.
6. Install rocker arm shaft and pushrods. See «INSTALLATION»(ref-288237-S23627810702008062000000) .
7. Tighten the rocker shaft bolts to 22 N.m (195 in. lbs.) torque, using the rocker shaft torque sequence. 1 - PUSH ROD RETAINER FASTENER 2 - PUSH ROD RETAINER 9070
8. Remove special tool# 9070, pushrod retaining plate (1), if used. 1 - CYLINDER HEAD COVER 2 - GASKET 3 - FASTENERS 4 - CYLINDER HEAD 5 - HEAD GASKET
9. Install cylinder head cover (1).
10. Tighten cylinder head cover bolts and double ended studs. (See «INSTALLATION»(ref-288237-S32582981352008062000000) ) .
11. Install spark plugs.
12. Install ignition coil on plug (2), and torque fasteners (3) to 7 N.m (62 in. lbs)
13. Install ignition coil connectors (4).
14. Install air intake resonator.
15. Install air cleaner assembly.
16. Connect negative battery cable.