Cylinder Head Assembly: Service and Repair
REMOVAL - CYLINDER HEAD
1. Perform fuel system pressure release procedure before attempting any repairs.
2. Remove clean air hose and air cleaner housing.
3. Disconnect negative cable from battery.
4. Drain cooling system.
5. Remove upper intake manifold.
6. Remove fastener attaching dipstick tube to lower intake manifold (Fig. 24) or (Fig. 25).
7. Turbocharger equipped vehicles: Remove lower intake manifold support bracket (Fig. 25).
8. Disconnect the fuel supply line quick-connect at the fuel rail assembly.
9. Remove heater tube support bracket from cylinder head.
10. Remove upper radiator hose. Disconnect heater hoses from thermostat housing.
11. Disconnect engine coolant temperature sensor connector.
12. Remove accessory drive belts.
13. Disconnect exhaust pipe from manifold.
14. Turbocharger equipped vehicles: (Fig. 26)
^ Remove turbocharger heat shields
^ Remove elbow support bracket
^ Remove turbocharger support bracket
^ Remove elbow
15. Turbocharger equipped vehicles: (Fig. 27).
^ Remove oil return tube
^ Remove oil supply line
^ Remove coolant supply line
^ Remove coolant return line
16. Disconnect ignition coil wiring connector. Remove ignition coil and plug wires from engine.
17. Disconnect camshaft position sensor wiring connector.
18. Remove timing belt and camshaft sprockets.
19. Remove timing belt idler pulley and rear timing belt cover.
20. Non-Turbo equipped vehicles: Remove fasteners securing power steering pump fluid reservoir/ bracket to cylinder head.
21. Remove cylinder head cover.
22. Remove camshafts.
23. Remove rocker arms.
24. Remove cylinder head bolts in the reverse sequence of tightening (Fig. 33).
25. Remove cylinder head from engine block.
26. Inspect and clean cylinder head and block sealing surfaces. Refer to Cleaning and Inspection for procedures.
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. 28).
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. 29).
5. Check valve guide height (Fig. 30).
INSTALLATION - CYLINDER HEAD
NOTE: The Cylinder head bolts should be examined BEFORE reuse. If the threads are necked down, the bolts should be replaced (Fig. 31).
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 engine block with the part number facing up (Fig. 32). Ensure gasket is seated over the locating dowels in block.
2. Position cylinder head onto engine block.
3. Before installing the bolts, the threads should be lightly coated with engine oil.
4. Tighten the cylinder head bolts in the sequence shown in (Fig. 33). Using the 4 step torque-turn method, tighten according to the following values:
^ First: All to 34 Nm (25 ft. lbs.)
^ Second: All to 82 Nm (60 ft. lbs.)
^ Third: All to 82 Nm (60 ft. lbs.)
CAUTION: Do not use a torque wrench for the Fourth step.
^ Fourth: Turn all bolts an additional 1/4 Turn
5. Install rocker arms and camshafts.
6. Install cylinder head cover.
7. Install rear timing belt cover and timing belt idler pulley.
8. Install camshaft sprockets and timing belt.
9. Connect cam sensor wiring connector.
10. Install ignition coil and plug wires. Connect ignition coil wiring connector.
11. Non-Turbo equipped vehicles: Install power steering pump reservoir/bracket to cylinder head.
12. Turbocharger equipped vehicles: (Fig. 27).
^ Install coolant return line
^ Install coolant supply line
^ Install oil supply line
^ Install oil return tube
13. Turbocharger equipped vehicles: (Fig. 26)
^ Install elbow
^ Install turbocharger support bracket
^ Install elbow support bracket
^ Install turbocharger heat shields
14. Install exhaust pipe to manifold. Tighten fasteners to 28 Nm (20 ft. lbs.).
15. Install accessory drive belts.
16. Connect engine coolant temperature sensor connector.
17. Connect upper radiator hose. Connect heater hoses to thermostat housing.
18. Install heater tube support bracket to cylinder head.
19. Turbocharger equipped vehicles: Install lower intake manifold support bracket (Fig. 25).
20. Install fastener attaching dipstick tube to lower intake manifold (Fig. 24) or (Fig. 25).
21. Connect fuel supply line quick-connect at the fuel rail assembly.
22. Install upper intake manifold.
23. Fill cooling system.
24. Connect negative cable to battery.
25. Install clean air hose and air cleaner housing.