Cylinder Head Assembly: Service and Repair
*** THIS ARTICLE INCLUDES REVISED UPDATES, FOR ADDITIONAL INFORMATION NOT INCLUDED HERE, REFER TO TSB #98-4-9, DATED MARCH 2, 1998 ***REMOVAL
1. Drain cooling system.
2. Disconnect negative battery cable.
3. Remove air cleaner assembly including air intake ducting and heat tube.
4. Remove accessory drive belt.
5. Perform the following procedures for Left Hand cylinder head removal:
a. Remove the oil filler cap.
b. Remove the power steering pump, leaving the hoses connected. Place the pump and bracket assembly aside in a position to prevent fluid loss.
c. Remove air conditioning mounting brackets. Leave the air conditioning hoses connected and position the compressor aside.
d. Remove the alternator and bracket assembly.
6. Perform the following procedures for Right Hand cylinder head removal:
a. Disconnect the thermactor air control valve or bypass valve hose assembly at the air pump.
b. Disconnect thermactor tube support bracket from rear of cylinder head.
c. Remove the accessory drive idler.
d. Remove the thermactor pump pulley. Remove the thermactor pump.
7. Remove the upper intake manifold.
8. Remove the rocker arm covers. Note location of spark plug wire routing clip stud bolts.
NOTE: Do not use excess force when loosening rocker arm cover as cover may become damaged.
9. Remove the fuel injector rail assembly.
10. Remove the lower intake manifold.
11. Remove the exhaust manifold(s).
12. Loosen the rocker arm bolts enough to allow rocker arm to be lifted off the push rod and rotate to one side.
13. Remove the push rods. Identify position of each rod.
NOTE: Push rods should be installed in their original position during reassembly.
14. Remove the cylinder head attaching bolts and discard.
15. Remove the cylinder head(s).
16. Remove and discard old cylinder head gasket(s).
INSTALLATION
NOTE: Lightly oil all bolt and stud bolt threads before installation except those specifying special sealant.
1. Clean the cylinder head, intake manifold, valve cover and block surfaces. If the cylinder head was removed for a cylinder head gasket replacement, check flatness of cylinder head and block gasket surfaces.
2. Position new head gasket(s) onto the cylinder block using dowels for alignment.
3. Position the cylinder head(s) onto the block.
NOTE: This engine uses "Torque To Yield Bolts". Always use new cylinder head bolts to ensure leak-tight assembly. Torque retention with used bolts can vary, which may result in coolant or compression leakage at the cylinder head mating surface.
4. Apply a thin coating of pipe sealant D8AZ-19554-A or equivalent to the shorter cylinder head bolts which are installed on the exhaust manifold side of the cylinder head. Do not apply pipe sealant to long bolts which are installed on the intake manifold side of the cylinder head.
FWD 3.8L:
5. Reassemble and torque the new head bolts to the following specifications. Torque all bolts in numerical sequence in three steps as follows:
a. 20 N.m (15 lb-ft)
b. 40 N.m (30 lb-ft)
c. 50 N.m (37 lb-ft)
6. In numerical sequence, retorque the bolts per the following Steps:
LONG BOLTS (Bolt Numbers 1, 3, 5, 7):
a. Loosen long bolt and back out 2-3 turns.
b. Retorque long bolt to 40-50 N.m (30-37 lb-ft).
c. Rotate long bolt an additional 175-185 degrees (approximately 1/2 turn).
d. Go to the next bolt in sequence.
SHORT BOLTS (Bolt Numbers 2, 4, 6, 8):
a. Loosen short bolt and back out 2-3 turns.
b. Retorque short bolt to 20-30 N.m (15-22 lb-ft).
c. Rotate short bolt an additional 175-185 degrees (approximately 1/2 turn).
d. Go to the next bolt in sequence.
7. Dip each push rod end in heavy engine oil and install in their original position.
8. Position rocker arms over pushrods. For each valve, rotate crankshaft until lifter rests on the heel (base circle) of the camshaft lobe before tightening rocker arm attaching bolts. Tighten rocker arm bolts to 5 Nm (43 lb-in) maximum.
9. After all rocker arm assemblies are installed and tightened as explained above, lubricate all rocker arm assemblies with heavy engine oil. For final tightening camshaft may be in any position, tighten the rocker arm bolts to 25-35 Nm (19-25 lb-ft).
10. Perform a valve clearance check.
11. Install exhaust manifold(s).
Intake Manifold:
12. Install lower intake manifold.
13. Install fuel injector rail assembly.
14. Position valve cover and gasket on cylinder head and install attaching bolts. Tighten to 8-11 Nm (71-101 lb-in).
15. Install upper intake manifold.
16. Perform the following procedures for Left Hand cylinder head installation:
a. Install air conditioning compressor mounting and support brackets.
b. Install power steering pump mounting and support brackets.
c. Install alternator and mounting brackets.
17. Perform the following procedures for Right Hand cylinder head installation:
a. Install the thermactor pump and pump pulley.
b. Install accessory drive idler assembly.
c. Install thermactor tube support bracket to rear of the cylinder head.
d. Install thermactor air control valve or bypass valve hose.
18. Connect the negative battery cable.
19. Fill cooling system with specified coolant.
20. START engine and check for coolant, fuel and oil leaks.
21. Check and, if necessary, adjust curb idle speed.
22. Install air cleaner assembly including air intake ducting and heat tube.