Cylinder Head Assembly: Service and Repair

CYLINDER HEAD

REMOVAL
1. Disconnect the negative cable from the battery.
2. Drain cooling system.





3. Remove the heat shields (Fig. 7).
4. Remove the intake manifold-to-generator bracket support rod. Remove the generator.
5. Remove closed crankcase ventilation system.
6. Disconnect the evaporation control system.
7. Remove the air cleaner.
8. Perform the Fuel System Pressure release procedure. Disconnect the fuel line.
9. Disconnect accelerator linkage and if so equipped, the speed control and transmission kickdown cables.





10. Remove coil pack and bracket (Fig. 8).
11. Disconnect the coil wires.
12. Disconnect heat indicator sending unit wire.
13. Disconnect heater hoses and bypass hose.
14. Remove upper intake manifold and throttle body as an assembly.
15. Remove cylinder head covers and gaskets.
16. Remove the EGR tube. Discard the gasket, for right side only.
17. Remove lower intake manifold. Discard the flange side gaskets and the front and rear cross-over gaskets.
18. Disconnect exhaust pipe from exhaust manifold.
19. Remove exhaust manifolds and gaskets.
20. Remove rocker arm assemblies and push rods. Identify to ensure installation in original locations.
21. Remove the head bolts from each cylinder head and remove cylinder heads. Discard the cylinder head gasket.
22. Remove spark plugs.

CLEANING
Clean all surfaces of cylinder block and cylinder heads. Be sure material does not fall into the lifters and surrounding valley.

Clean cylinder block front and rear gasket surfaces using a suitable solvent.

Clean the exhaust manifold to cylinder head mating areas.

INSPECTION
Inspect all surfaces with a straightedge if there is any reason to suspect leakage. The out-of-flatness specifications are 0.0007 mm/mm (0.0004 inch/inch), 0.127 mm/152 mm (0.005 inch/6 inches) any direction or 0.254 mm (0.010 in.) overall across head. If exceeded, either replace head or lightly machine the head surface.

The cylinder head surface finish should be 1.78 - 4.57 microns (15 - 80 microinches).

Inspect push rods. Replace worn or bent rods.

Inspect rocker arms. Replace if worn or scored.

INSTALLATION
1. Position the new cylinder head gaskets onto the cylinder block.
2. Position the cylinder heads onto head gaskets and cylinder block.





3. Tighten the cylinder head bolts in two steps (Fig. 9)
- Step 1-Tighten all cylinder head bolts, in sequence, to 58 Nm (43 ft. lbs.) torque.
- Step 2-Tighten all cylinder head bolts, in sequence, to 143 Nm (105 ft. lbs.) torque.

CAUTION: When tightening the rocker arm bolts, make sure the piston in that cylinder is NOT at TDC. Contact between the valves and piston could occur.

4. Install push rods and rocker arm assemblies in their original position.
5. Install lower intake manifold.
6. Install the upper intake manifold onto the lower intake manifold.
7. Install the exhaust manifolds and new gaskets.
8. Install exhaust pipe to the exhaust manifold. Tighten the bolts to 34 Nm (25 ft. lbs.) torque.
9. Using a new gasket, position the EGR tube to the intake manifold and the exhaust manifold. Tighten the EGR tube nut to 34 Nm (25 ft. lbs.) torque. Tighten the bolts to 20 Nm (174 in. lbs.) torque.
10. Install the heat shields and the washers. Make sure that heat shields tabs hook over the exhaust gasket. Tighten the nuts to 15 Nm (132 in. lbs.) torque.
11. Adjust and Install the spark plugs.
12. Install coil packs and bracket. Tighten the bracket bolts to 21 Nm (190 in. lbs.) torque. Connect the coil wires.
13. Connect heat indicator sending unit wire.
14. Connect the heater hoses and bypass hose.
15. Connect the accelerator linkage and if so equipped, the speed control and transmission kickdown cables.
16. Install the fuel line.
17. Install the generator and drive belt.
18. Install the intake manifold-to-generator bracket support rod. Tighten the bolts to 41 Nm (30 ft. lbs.) torque.
19. The cylinder head cover gasket can be used again. Install the gasket onto the head rail. For the left side the number tab is at the front of engine with the number up. For the right side the number tab is at the rear of engine with the number up.

CAUTION: The cylinder head cover fasteners have a special plating. DO NOT use alternative fasteners.

20. Install cylinder head cover.
21. Install closed crankcase ventilation system.
22. Connect the evaporation control system.
23. Install the air cleaner.
24. Fill cooling system.
25. Connect the negative cable to the battery.
26. Check for leaks (fuel, oil, antifreeze, etc.).