Cylinder Head Assembly: Service and Repair
HEAD(S)-CYLINDERREMOVAL
NOTE: Care must be taken to protect the intake manifold and cylinder head covers powder coating from scrapes and abrasions. This procedure covers either the left or right cylinder head.
The aluminum alloy cylinder head shown in is held in place by 12, 1/2 inch bolts (5) and 8, 1/4 inch bolts (4).
1. Release the fuel pressure.
2. Disconnect negative battery cable.
3. Disconnect the throttle body air inlet duct, IAT sensor, CCV hose and remove the air cleaner cover.
4. Drain the cooling system.
5. Raise and support the vehicle.
6. Disconnect the front exhaust pipe to exhaust manifold connection.
7. Lower the vehicle.
8. Remove intake manifold.
9. Disconnect the spark plug wires by pulling on the boot straight out in line with the spark plug. Dislodge spark plug retainers from the cylinder head cover studs and position the spark plug wires aside.
10. Disconnect the oil level indicator tube and set aside.
11. Disconnect CCV hoses from cylinder head covers.
12. Remove the cylinder head covers.
13. Remove exhaust manifold heat shields.
14. Remove exhaust manifold(s) and gasket(s).
NOTE: If rocker arms and push rods are to be reused, identify each component to ensure installation in original locations.
15. Remove the rocker arm and pedestal assemblies.
16. Remove push rods.
17. Remove the 12 head bolts and 8 cylinder head tappet gallery bolts from cylinder head(s).
18. Remove cylinder head(s) and gasket(s).
CLEANING AND INSPECTION
1. Before cleaning, check for leaks, damage and cracks.
2. Clean cylinder head and oil passages.
3. Check cylinder head for flatness.
4. Inspect all surfaces with a straightedge (2) if there is any reason to suspect leakage. If out-of-flatness exceeds 0.019 mm (0.00075 inch) times the span length in inches in any direction, either replace head or lightly machine the head surface. As an example, if a 12.0 inch span is 1.0 mm (0.004 inch) out-of-flat, allowable is 12 x 0.019 mm (0.00075 inch) equals 0.22 mm (0.009 inch). This amount of out-of-flat is acceptable. Maximum of 0.2 mm (0.008 inch) for grinding is permitted.
CAUTION: This is a combined total dimension of stock removal from cylinder head surface.
INSTALLATION - CYLINDER HEAD(S)
NOTE: This procedure covers either the left or right cylinder head.
1. Clean all surfaces of engine block and cylinder heads.
CAUTION: Remove all gasket material from cylinder head and block using a plastic scraper only. DO NOT use a metal scraper, as damage to sealing surface may occur.
NOTE: A multi-layer steel head gasket is used.
2. Install new gasket(s) on the engine block. Assure all coolant passages and bolt holes align properly.
CAUTION: Cylinder head bolts are coated, DO NOT oil.
3. Install cylinder head(s) over dowel pins. Install cylinder head bolts 1-12. Tighten cylinder head bolts 1-12 in the sequence shown in using a two step torque sequence:
a. First to 47 Nm (35 ft. lbs.).
b. Second to 122 Nm (90 ft. lbs.).
4. After cylinder head bolts 1-12 have been tightened to specifications, install and tighten cylinder head tappet gallery bolts A-H in sequence shown to 11 Nm (95 inch lbs.).
5. Inspect the push rods. Replace worn or bent push rods as necessary.
6. Install push rods. Install rocker arms and pedestal assemblies into their original positions. Ensure push rods are seated properly under each rocker arm. Tighten rocker arm bolts to 35 Nm (26 ft. lbs.).
7. Install exhaust manifold(s) and gasket(s).
8. Install exhaust manifold heat shields.
9. Install cylinder head covers.
10. Position and install the oil level indicator tube. Tighten fastener to 11 Nm (95 inch lbs.).
11. Connect CCV hoses to cylinder head covers.
12. Install the spark plug wires and plug wire retainers.
13. Install intake manifold.
14. Raise and support the vehicle.
15. Connect the exhaust system to the exhaust manifolds.
16. Drain the engine oil.
17. Lower the vehicle.
18. Fill engine oil to the proper level.
19. Fill the cooling system.
20. Connect negative battery cable.
21. Install the air cleaner cover, throttle inlet duct and connect the IAT sensor and CCV hose.
22. Start engine and inspect for leaks.