Cylinder Head Assembly: Service and Repair

CYLINDER HEAD GASKET

REMOVAL
1. Perform fuel system pressure release procedure before attempting any repairs.
2. Disconnect inlet air temperature sensor and make-up air hose.
3. Remove clean air hose and air cleaner housing.
4. Disconnect negative cable from battery.
5. Drain cooling system.
6. Remove upper intake manifold.





7. Remove fastener attaching dipstick tube to lower intake manifold (Fig. 18).
8. Disconnect the fuel supply line quick-connect at the fuel rail assembly.
9. Remove heater tube support bracket from cylinder head.
10. Disconnect upper radiator and heater supply hoses from coolant outlet connections.
11. Disconnect engine coolant temperature sensor connector.
12. Remove accessory drive belts.
13. Disconnect exhaust pipe from manifold.
14. Disconnect ignition coil wiring connector.
Remove ignition coil and plug wires from engine.





15. Disconnect cam sensor wiring connector (Fig. 19).
16. Remove timing belt and camshaft sprockets.
17. Remove timing belt idler pulley and rear timing belt cover.
18. Remove fasteners securing power steering pump fluid reservoir/bracket to cylinder head.
19. Remove cylinder head cover.
20. Remove camshafts.
21. Remove rocker arms.





22. Remove cylinder head bolts in the reverse sequence of tightening (Fig. 25).
23. Remove cylinder head from engine block.
24. Inspect and clean cylinder head and block sealing surfaces.

NOTE: Ensure cylinder head bolt holes in the block are clean, dry (free of residual oil or coolant), and threads are not damaged.

CLEANING
To ensure engine gasket sealing, proper surface preparation must be performed, especially with the use of aluminum engine components and multi-layer steel cylinder head gaskets. Refer to Engine/Service and Repair/Procedures/Standard Procedures/Engine Gasket Surface Preparation. Engine Gasket Surface Preparation

NOTE: Multi-Layer Steel (MLS) head gaskets require a scratch free sealing surface.

Remove all gasket material from cylinder head and block.
Be careful not to gouge or scratch the aluminum head sealing surface.
Clean all engine oil passages.

INSPECTION





1. Cylinder head must be flat within 0.1 mm (0.004 inch) (Fig. 20).
2. Inspect camshaft bearing journals for scoring.
3. Remove carbon and varnish deposits from inside of valve guides with a reliable guide cleaner.





4. Using a small hole gauge and a micrometer, measure valve guides in 3 places top, middle and bottom (Fig. 21).
Replace guides if they are not within specification.





5. Check valve guide height (Fig. 22).

INSTALLATION





NOTE: The Cylinder head bolts should be examined BEFORE reuse. If the threads are necked down, the bolts should be replaced (Fig. 23).

Necking can be checked by holding a scale or straight edge against the threads. If all the threads do not contact the scale, the bolt should be replaced.





1. Position the new cylinder head gasket on cylinder block with the part number facing up (Fig. 24).
Ensure gasket is seated over the locating dowels in block.
2. Before installing the bolts, the threads should be lightly coated with engine oil.





3. Tighten the cylinder head bolts in the sequence shown in (Fig. 25). Using the 4 step torque-turn method, tighten according to the following values:
- First: All to 34 Nm (25 ft. lbs.)
- Second: All to 68 Nm (50 ft. lbs.)
- Third: All to 68 Nm (50 ft. lbs.)

CAUTION: Do not use a torque wrench for the Fourth step.

- Fourth: Turn all bolts an additional 1/4 Turn

4. Install rocker arms and camshafts.
5. Install cylinder head cover.
6. Install rear timing belt cover and timing belt idler pulley.
7. Install camshaft sprockets and timing belt.
8. Connect cam sensor wiring connector (Fig. 19).
9. Install ignition coil and plug wires. Connect ignition coil wiring connector.
10. Install power steering pump reservoir/bracket to cylinder head.
11. Install exhaust pipe to manifold. Tighten fasteners to 28 Nm (20 ft. lbs.).
12. Install accessory drive belts.
13. Connect engine coolant temperature sensor connector.
14. Connect upper radiator and heater supply hoses to coolant outlet connections.
15. Install heater tube support bracket to cylinder head.
16. Install fastener attaching dipstick tube to lower intake manifold (Fig. 18).
17. Connect fuel supply line quick-connect at the fuel rail assembly.
18. Install upper intake manifold.
19. Fill cooling system.
20. Connect negative cable to battery.
21. Install clean air hose and air cleaner housing.
22. Connect inlet air temperature sensor and make-up air hose.