Cylinder Head Assembly: Service and Repair
REMOVALNOTE: This procedure can be done with the engine in or out of the vehicle.
1. Disconnect the battery negative cable.
WARNING: DO NOT REMOVE THE CYLINDER BLOCK DRAIN PLUGS OR LOOSEN THE RADIATOR DRAIN COCK WITH THE SYSTEM HOT AND PRESSURIZED BECAUSE SERIOUS BURNS FROM THE COOLANT CAN OCCUR.
2. Drain the coolant and disconnect the hoses at the engine thermostat housing and the water pump inlet. DO NOT waste reusable coolant. If the solution is clean and is being drained only to service the engine or cooling system, drain the coolant into a clean container for reuse.
3. Remove the air cleaner assembly.
4. Remove the cylinder head cover.
5. Remove the capscrews, bridge and pivot assemblies and rocker arms.
6. Remove the push rods. Retain the push rods, bridges, pivots and rocker arms in the same order as removed.
7. Remove the accessory drive belt.
8. Remove the A/C compressor mounting bolts and secure the compressor to the side.
9. Remove the power steering pump and bracket from the intake manifold and water pump. Set the pump and bracket aside. DO NOT disconnect the hoses.
10. Perform the Fuel System Pressure Release procedure.
11. Disconnect the fuel supply line at the fuel rail.
12. Remove the intake and exhaust manifolds from the engine cylinder head.
13. Disconnect the coil rail electrical connectors and remove the coil rail.
14. Remove spark plugs.
15. Disconnect the temperature sending unit wire connector.
16. Remove the engine cylinder head bolts. Bolt No. 14 cannot be removed until the head is moved forward (Fig. 11). Pull bolt No. 14 out as far as it will go and then suspend the bolt in this position (tape around the bolt).
17. Remove the engine cylinder head and gasket (Fig. 11).
18. If this was the first time the bolts were removed, put a paint dab on the top of the bolt. If the bolts have a paint dab on the top of the bolt or it isn't known if they were used before, discard the bolts.
19. Stuff clean lint free shop towels into the cylinder bores.
NOTE: If the valves, springs, or seals are to be inspected/replaced at this time.
CLEANING
Thoroughly clean the engine cylinder head and cylinder block mating surfaces. Clean the intake and engine exhaust manifold and engine cylinder head mating surfaces. Remove all gasket material and carbon.
Check to ensure that no coolant or foreign material has fallen into the tappet bore area.
Remove the carbon deposits from the combustion chambers and top of the pistons.
INSPECTION
Use a straightedge and feeler gauge to check the flatness of the engine cylinder head and block mating surfaces.
INSTALLATION
NOTE: This procedure can be done with the engine in or out of the vehicle.
The engine cylinder head gasket is a composition gasket. The gasket is to be installed DRY. DO NOT use a gasket sealing compound on the gasket.
If the engine cylinder head is to be replaced and the original valves used, measure the valve stem diameter. Only standard size valves can be used with a service replacement engine cylinder head unless the replacement head valve stem guide bores are reamed to accommodate oversize valve stems. Remove all carbon buildup and reface the valves.
1. Remove the shop towels from the cylinder bores. Coat the bores with clean engine oil.
2. Position the engine cylinder head gasket (with the numbers facing up) using the alignment dowels in the cylinder block, to position the gasket.
CAUTION: Engine cylinder head bolts should be reused only once. Replace the head bolts if they were used before or if they have a paint dab on the top of the bolt.
3. With bolt No. 14 held in place (tape around bolt), install the engine cylinder head over the same dowels used to locate the gasket. Remove the tape from bolt No. 14.
4. Coat the threads of stud bolt No. 11 with Loctite 592 sealant, or equivalent.
5. Tighten the engine cylinder head bolts in sequence according to the following procedure (Fig. 12).
CAUTION: During the final tightening sequence, bolt No. 11 will be tightened to a lower torque than the rest of the bolts. DO NOT overtighten bolt No. 11.
a. Tighten all bolts in sequence (1 through 14) to 30 Nm (22 ft. lbs.) torque.
b. Tighten all bolts in sequence (1 through 14) to 61 Nm (45 ft. lbs.) torque.
c. Check all bolts to verify they are set to 61 Nm (45 ft. lbs.) torque.
d. Tighten bolts in sequence:
- Bolts 1 through 10 to 149 Nm (110 ft. lbs.) torque.
- Bolt 11 to 135 Nm (100 ft. lbs.) torque.
- Bolts 12 through 14 to 149 Nm (110 ft. lbs.) torque.
CYLINDER HEAD BOLTS
e. Check all bolts in sequence to verify the correct torque.
f. If not already done, clean and mark each bolt with a dab of paint after tightening. Should you encounter bolts which were painted in an earlier service operation, replace them.
6. Install the spark plugs and tighten to 37 Nm (27 ft. lbs.) torque.
7. Connect the temperature sending unit wire connector.
8. Install the ignition coil rail and coil rail electrical connectors.
9. Install the intake and exhaust manifolds.
10. Install the fuel line and the vacuum advance hose.
11. Attach the power steering pump and bracket.
12. Install the push rods, rocker arms, pivots and bridges in the order they were removed.
13. Install the engine cylinder head cover.
14. Attach the air conditioner compressor mounting bracket to the engine cylinder head and block. Tighten the bolts to 40 Nm (30 ft. lbs.) torque.
15. Attach the air conditioning compressor to the bracket. Tighten the bolts to 27 Nm (20 ft. lbs.) torque.
CAUTION: The serpentine drive belt must be routed correctly. Incorrect routing can cause the water pump to turn in the opposite direction causing the engine to overheat.
16. Install the serpentine drive belt.
17. Install the air cleaner and ducting.
18. Connect the hoses to the engine thermostat housing and fill the cooling system to the specified level.
19. The automatic transmission throttle linkage and cable must be adjusted after completing the engine cylinder head installation.
20. Install the temperature sending unit and connect the wire connector.
21. If equipped with air conditioning, install A/C compressor and charge A/C system.
22. Connect negative cable to battery.
WARNING: USE EXTREME CAUTION WHEN THE ENGINE IS OPERATING. DO NOT STAND IN DIRECT LINE WITH THE FAN. DO NOT PUT HANDS NEAR THE PULLEYS, BELTS OR FAN. DO NOT WEAR LOOSE CLOTHING.
23. Operate the engine with the radiator cap off. Inspect for leaks and continue operating the engine until the engine thermostat opens. Add coolant, if required.