17. Install the intake manifold.
18. Using a new gasket, install throttle body (Refer to
14 - FUEL SYSTEM/FUEL INJECTION/THROT-
TLE BODY - INSTALLATION).
19. Install the generator (2) and wire connections
(Refer to 8 - ELECTRICAL/CHARGING/GENERA-
TOR - INSTALLATION).
20. Install a/c compressor (2) (Refer to 24 - HEATING
& AIR CONDITIONING/PLUMBING/A/C COM-
PRESSOR - INSTALLATION).
CYLINDER HEAD
OPERATION—CYLINDER HEAD
The cylinder head closes the combustion chamber allowing the pistons to compress the air fuel mixture to the cor-
rect ratio for ignition. The valves located in the cylinder head open and close to either allow clean air into the com-
bustion chamber or to allow the exhaust gases out, depending on the stroke of the engine.
DIAGNOSIS AND TESTING—CYLINDER HEAD GASKET FAILURE
A cylinder head gasket leak can be located between adjacent cylinders or between a cylinder and the adjacent
water jacket.
Possible indications of the cylinder head gasket leaking between adjacent cylinders are:
− Loss of engine power
− Engine misfiring
− Poor fuel economy
Possible indications of the cylinder head gasket leaking between a cylinder and an adjacent water jacket are:
− Engine overheating
− Loss of coolant
− Excessive steam (white smoke) emitting from exhaust
− Coolant foaming
CYLINDER-TO-CYLINDER LEAKAGE TEST
To determine if an engine cylinder head gasket is leaking between adjacentcylinders, follow the procedures in Cyl-
inder Compression Pressure Test in this section. An engine cylinder head gasket leaking between adjacent cylinders
will result in approximately a 50–70% reduction in compression pressure.
CYLINDER-TO-WATER JACKET LEAKAGE TEST
WARNING: USE EXTREME CAUTION WHEN THE ENGINE IS OPERATING WITH COOLANT PRESSURE CAP
REMOVED.
VISUAL TEST METHOD
With the engine cool, remove the coolant pressure cap. Start the engine andallow it to warm up until thermostat
opens.
If a large combustion/compression pressure leak exists, bubbles will be visible in the coolant.
COOLING SYSTEM TESTER METHOD
WARNING: WITH COOLING SYSTEM TESTER IN PLACE, PRESSURE WILL BUILD UP FAST.EXCESSIVE
PRESSURE BUILT UP, BY CONTINUOUS ENGINE OPERATION, MUST BE RELEASED TO A SAFE PRESSURE
POINT. NEVER PERMIT PRESSURE TO EXCEED 138 kPa (20 psi).
Install Cooling System Tester 7700 or equivalent to pressure cap neck. Start the engine and observe the tester’s
pressure gauge. If gauge pulsates with every power stroke of a cylinder a combustion pressure leak is evident.
CHEMICAL TEST METHOD
Combustion leaks into the cooling system can also be checked by using Bloc-Chek Kit C-3685-A or equivalent.
Perform test following the procedures supplied with the tool kit.
3. Place a shop towel around the fuel injectors to catch any fluid that may possibly be under pressure in the cyl-
inder head. Remove the fuel injectors (Refer to 14 - FUEL SYSTEM/FUEL INJECTION/FUEL INJECTOR -
REMOVAL).
4. With all injectors removed, rotatethe crankshaft using the crankshaftbarring tool (PN 7471–B).
5. Identify the fluid in the cylinders (coolant, fuel, oil, etc.).
6. Be sure all fluid has been removed from the cylinders.
7. Repair engine or components as necessary to prevent this problem from occurring again.
8. Squirt a small amount of engine oil into the cylinders to lubricate the walls. This will prevent damage on restart.
9. Install fuel injectors (Refer to 14 - FUEL SYSTEM/FUEL INJECTION/FUEL INJECTOR - INSTALLATION).
10. Drain engine oil. Remove and discard the oil filter (Refer to 9 - ENGINE/LUBRICATION/OIL FILTER -
REMOVAL).
11. Installthedrainplug.Tightentheplugto50Nꞏm(37ft.lbs.)torque.
12. Install a new oil filter (Refer to 9 - ENGINE/LUBRICATION/OIL FILTER - INSTALLATION).
13. Fill engine crankcase with the specified amount and grade of oil (Referto LUBRICATION & MAINTENANCE/
FLUID TYPES - SPECIFICATIONS).
14. Connect the negative cable(s) to the battery.
15. Start the engine and check for any leaks.
REMOVAL - ENGINE
1. Disconnect both battery negative cables.
2. Disconnect engine grid heater harness at grid
heater relays.
3. Disconnect electrical connections from rear of alter-
nator.
4. Recover A/C refrigerant. (Refer to 24 - HEATING &
AIR CONDITIONING/PLUMBING - STANDARD
PROCEDURE).
5. Raise vehicle on a hoist.
6. Drain engine coolant (Refer to 7 - COOLING -
STANDARD PROCEDURE).
7. Remove engine oil drain plug and drain engine oil.
8. Reinstall drain plug. Tighten to 50 Nꞏm (37 ft. lbs.)
torque.
9. Lower the vehicle.
10. Remove fan (3) and fan drive (2). Refer to (Refer
to 7 - COOLING/ENGINE/RADIATOR FAN -
REMOVAL).
CAMSHAFT & BEARINGS (IN BLOCK)
REMOVAL
CAMSHAFT BEARINGS
NOTE: Measure the diameter of each bore. If the camshaft bore for the cam bushing is worn beyond the
limit, install a new service bushing. Inspect the rest of the camshaft bores for damage or excessive wear.If
the bores without a bushing are worn beyond the limit, the engine must be removed for machining and
installation of service bushings. If badly worn, replace the cylinder block.
1. Remove the camshaft (Refer to 9 - ENGINE/ENGINE BLOCK/CAMSHAFT & BEARINGS (IN BLOCK) -
REMOVAL).
2. Remove the bushing from the No.1 bore.
3. Mark the cylinder block so you can align the oil hole in the cylinder blockwith the oil hole in the bushing.
CAMSHAFT
1. Disconnect both battery negative cables.
2. Recover A/C refrigerant (if A/C equipped) (Refer to 24 - HEATING & AIR CONDITIONING/PLUMBING - STAN-
DARD PROCEDURE).
3. Raise vehicle on hoist.
4. Drain engine coolant into container suitable for re-use (Refer to 7 - COOLING - STANDARD PROCEDURE).
5. Lower vehicle.
6. Remove radiator upper hose.
7. Remove viscous fan/drive/shroud assembly (Refer to 7 - COOLING/ENGINE/RADIATOR FAN - REMOVAL).
8. Disconnect the coolant recovery bottle hose from the radiator filler neck.
9. Disconnect lower radiator hose from radiator outlet.
10.Automatic Transmission models:Disconnect transmission oil cooler lines from front of radiator using Special
Tool 6931 (unless equipped with finger-release disconnect).
11. Remove radiator mounting screws and lift radiator out of engine compartment.
12. Remove upper radiator support panel.
13. If A/C equipped, disconnect A/C condenser refrigerant lines.
14. Disconnect charge air cooler piping from the cooler inlet and outlet.
15. Remove the two charge air cooler mounting bolts.
16. Remove charge air cooler (and A/C condenser if equipped) from vehicle.
17. Remove accessory drive belt (Refer to 7 - COOLING/ACCESSORY DRIVE/DRIVE BELTS - REMOVAL).
18. Remove accessory drive belt tensioner.
19. Remove the fan support/hub assembly.
20. Remove crankshaft damper and speed indicator ring (Refer to 9 - ENGINE/ENGINE BLOCK/VIBRATION
DAMPER - REMOVAL).
21. Remove the gear cover-to-housing bolts and gently pry the cover away from the housing, taking care not to mar
the sealing surfaces. Remove dust seal with cover.
22. Using Special Tool 7471–B Crankshaft Barring Tool, rotate the crankshaft to align the timing marks on the
crankshaft and the camshaft gears.
23. Remove the cylinder head cover (Refer to 9 - ENGINE/CYLINDER HEAD/CYLINDER HEAD COVER(S) -
REMOVAL).
12. Install gear housing cover (Refer to 9 - ENGINE/VALVE TIMING/GEAR HOUSING COVER - INSTALLATION).
Install front crankshaft dust seal.
13. Install the crankshaft damper with the speed indicator ring (Refer to 9- ENGINE/ENGINE BLOCK/VIBRATION
DAMPER - INSTALLATION).
14. Install the fan support/hub assembly Refer to (Refer to 7 - COOLING/ENGINE/RADIATOR FAN - INSTALLA-
TION).
15. Install the power steering pump.
16. Install accessory drive belt tensioner. Torque bolt to 43 Nꞏm (32 ft. lbs.).
17. Install the accessory drive belt (Refer to 7 - COOLING/ACCESSORY DRIVE/DRIVE BELTS - INSTALLATION).
18. Install the charge air cooler (with a/c condenser and auxiliary transmission oil cooler, if equipped) and tighten
the mounting bolts to 2 Nꞏm (17 in. lbs.) torque.
19. Connect charge air cooler inlet and outlet pipes. Tighten clamps to 11 Nꞏm (95 in. lbs.) torque.
20. Install the radiator upper support panel.
21. Close radiator petcock and lower the radiator into the engine compartment. Tighten the mounting bolts to 11
Nꞏm (95 in. lbs.) torque.
22. Raise vehicle on hoist.
23. Connect radiator lower hose and install clamp.
24. Connect transmission auxiliary oil cooler lines (if equipped).
25. Lower vehicle.
26. Install the fandrive/shroud assembly. (Refer to 7 - COOLING/ENGINE/RADIATOR FAN - INSTALLATION)
27. Install the coolant recovery and windshield washer fluid reservoirs to the fan shroud.
28. Connect the coolant recovery hose to the radiator filler neck.
29. Add engine coolant (Refer to 7 - COOLING - STANDARD PROCEDURE).
30. Charge A/C system with refrigerant (if A/C equipped) (Refer to 24 - HEATING & AIR CONDITIONING/PLUMB-
ING - STANDARD PROCEDURE).
31. Connect the battery negative cables.
32. Start engine and check for engine oil and coolant leaks.
3. Clean spark plug recesses with compressed air.
4. Remove the spark plugs.
5. Remove the oil fill cap.
6. Remove the air cleaner.
7. Calibrate the tester according to the manufacturer’s instructions. The shop air source for testing should maintain
483 kPa (70 psi) minimum, 1,379 kPa (200 psi) maximum, with 552 kPa (80 psi) recommended.
8. Perform the test procedures on each cylinder according to the tester manufacturer’s instructions. While testing,
listen for pressurized air escaping through the throttle body, tailpipe and oil filler cap opening. Check for bubbles
in the coolant pressure bottle.
All gauge pressure indications should be equal, with no more than 25 percent leakage per cylinder.
FOR EXAMPLE:At 552 kPa (80 psi) input pressure, a minimum of 414 kPa (60 psi) should be maintained in the
cylinder.
CYLINDER HEAD GASKET FAILURE DIAGNOSIS
A cylinder head gasket leak can be located between adjacent cylinders, between a cylinder and the adjacent water
jacket, or an external coolant leak may be present.
Possible indications of the cylinder head gasket leaking between adjacent cylinders are:
Loss of engine power
Engine misfiring
Poor fuel economy
Possible indications of the cylinder head gasket leaking between a cylinder and an adjacent water jacket are:
Engine overheating
Loss of coolant
Excessive steam (white smoke) emitting from exhaust
Coolant foaming
CYLINDER-TO-CYLINDER LEAKAGE TEST
To determine if an engine cylinder head gasket is leaking between adjacentcylinders, follow the procedures in Cyl-
inder Compression Pressure Test in this section. An engine cylinder head gasket leaking between adjacent cylinders
will result in approximately a 50-70% reduction in compression pressure.Cylinders adjacent to each other will both
have low compression.
CYLINDER-TO-WATER JACKET LEAKAGE TEST
WARNING: Use extreme caution when the engine is operating with coolant pressure cap removed.
VISUAL TEST METHOD
With the engine cool, remove the coolant pressure cap. Start the engine andallow it to warm up until thermostat
opens.
If a large combustion/compression pressure leak exists, bubbles will be visible in the coolant.
COOLING SYSTEM TESTER METHOD
WARNING: With cooling system tester in place, pressure will build up fast.Excessive pressure built up, by
continuous engine operation, must be released to a safe pressure point. Never permit pressure to exceed
138 kpa (20 psi).
Install Cooling System Tester 7700 or equivalent to pressure cap neck. Start the engine and observe the tester’s
pressure gauge. If gauge pulsates with every power stroke of a cylinder a combustion pressure leak is evident.
17. Separate the ground strap (1) from the floor
board, above the right exhaust flange.
18. Lower the vehicle.
19. Discharge air conditioning system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING/RE-
FRIGERANT - STANDARD PROCEDURE).
20. Remove the upper radiator hose.
21. Disconnect windshield washer hose at the splice.
22. Remove radiator core support.
23. Disconnect the cooling fan harness connector
(Refer to 7 - COOLING/ENGINE/RADIATOR FAN
- REMOVAL).
24. Remove the radiator and radiator fan assembly
(Refer to 7 - COOLING/ENGINE/RADIATOR -
REMOVAL).
25. Remove the A/C condenser, cap and position the
hoses aside.
26. Disconnect the heater hoses at the top front cover
and at the lower coolant housing and position
aside.
27. Disconnect the oil cooler hoses from the engine
and position aside (Refer to 9 - ENGINE/LUBRI-
CATION/OIL COOLER & LINES - STANDARD
PROCEDURE).
28. Remove accessory drive belt (1).
29. Disconnect and remove generator.
30. Remove power steering pump mounting bolts and
set pump aside.
4. Install the exhaust manifold heat shield nuts (2)
and tighten to 6 Nꞏm (50 in. lbs.).
5. Connect the ground strap to the thermostat hous-
ing and route the electrical and purge harness
underneath the throttle body and attach the con-
nectors.
6. Connect the fuel vapor purge lines.
7. Properly route and connect the spark plug wires.
8. Connect the engine electrical harnesses.
9. Connect the brake booster vacuum hose, fuel line,
cruise control and accelerator cables.
10. Install the A/C lines at the A/C compressor (Refer
to 24 - HEATING & AIR CONDITIONING/PLUMB-
ING/A/C COMPRESSOR - REMOVAL).
11. Connect A/C clutch electrical connector (Refer to
24 - HEATING & AIR CONDITIONING/PLUMB-
ING/A/C COMPRESSOR - REMOVAL).
12. Install the power steering pump.
13. Install the generator.
14. Install the accessory drive belt.
15. Connect the heater hoses to the engine.
16. Install the radiator and cooling fan assembly.
17. Install the A/C condenser.
18. Connect the A/C lines to the condenser.
19. Connect the cooling fan electrical connector.
20. Connect the windshield washer hose at the splice.
21. Install the coolant recovery container.
22. Install the upper radiator hose.
23. Install the throttle body air inlet duct and the air
cleaner element cover.
24. Raise and support the vehicle.
25. Install transmission.
26. Install transmission bolts and tighten bolts to:
7/16 Transmission bolts and washers (2) - 68
Nꞏm (50 ft. lbs.)
Transmission to top of engine - 41 Nꞏm (30 ft.
lbs.)
Transmission to oil pan (3) - 30 Nꞏm (22 ft. lbs.)
27. Install drive shaft.