Cylinder Head Assembly: Service and Repair

REMOVAL
1. Drain engine cooling system, then disconnect battery ground cable.
2. Remove air cleaner outlet tube from throttle body as follows:
a. Disconnect wire harness from intake air temperature sensor, then crankcase ventilation tube from air cleaner outlet tube.
b. Loosen air cleaner tube clamps on outlet tube, then disconnect outlet tube from throttle body.
c. Disconnect outlet tube from mass airflow sensor, then remove tube.
3. Loosen drive belt tensioner, then remove drive belts.
4. On lefthand cylinder head, proceed as follows:
a. Remove oil filler cap.
b. Remove power steering pump front mounting bracket bolts.
c. Remove generator, then belt idler pulley.
d. Remove power steering pump/generator bracket bolts, then place pump/bracket assembly aside, with hoses connected, in position to prevent fluid leakage.
5. On righthand cylinder head, proceed as follows:
a. Remove drive belt.
b. Remove A/C mounting bracket bolts, then place A/C compressor aside with hoses connected.
c. Remove positive crankcase ventilation valve.
6. Remove upper intake manifold.
7. Remove valve cover.
8. Remove fuel injection supply manifold.
9. Remove lower intake manifold.
10. Remove exhaust manifolds.
11. Loosen rocker arm fulcrum bolts enough to allow rocker arm to be lifted off push rod, and rotate to one side.
12. Remove push rods, then identify position of each push rod. Push rods should be installed in their original positions during assembly.
13. Remove cylinder head bolts, then cylinder heads. Discard bolts.
14. Remove and discard old head gaskets.

INSTALLATION

CAUTION: Always use new cylinder head bolts to ensure a leak-proof assembly. Torque retention with used bolts can vary, which may result in coolant or compression leakage at cylinder head mating surface area.

1. Prepare cylinder head components as follows:
a. Lightly oil all bolts and stud bolt threads before installation, except those specifying special sealant.
b. Clean cylinder head, intake manifold, rocker arm cover and head gasket surfaces. If cylinder head was removed for head gasket replacement, check flatness of cylinder head and cylinder block gasket surfaces.
2. Position new head gasket(s) onto cylinder block using dowels for alignment, then position cylinder heads onto cylinder block.

FWD 3.8L:

3. Reassemble and tighten the new head bolts to the following specifications:
Tighten all bolts in numerical sequence, as shown, in three steps as follows:

- 20 Nm (15 lb-ft)
- 40 Nm (30 lb-ft)
- 50 Nm (37 lb-ft)

Caution: Do not loosen all of the bolts at the same time. Work on one bolt at a time in the sequence shown. Failure to loosen bolts in proper sequence could cause cylinder head to warp.

4. In numerical sequence, retighten the bolts per the fallowing steps:

Long Bolts:

a. Loosen the long bolt and back out 2-3 revolutions.
b. Retighten the long bolt to 40-50 Nm (29-37 lb-ft).
c. Rotate the long bolt an additional 180°.
d. Go to the next bolt in sequence.

Short Bolts:

a. Loosen the short bolt and back out 2-3 revolutions.
b. Retighten the short bolt to 15-25 Nm (11-18 lb-ft).
c. Rotate the short bolt an additional 180°.
d. Go to the next bolt in sequence.
5. Dip each push rod end in engine assembly lubricant D9AZ-19579-D or equivalent.
6. Install push rods in their original positions, then lubricate all rocker arms with engine assembly lubricant D9AZ-19579-D or equivalent.
7. Install rocker arms.
8. Install exhaust manifolds.
9. Install lower intake manifold.
10. Install fuel injection supply manifold.
11. Position valve cover on cylinder head and install bolts. Note location of ignition wire routing clip stud bolts.
12. Install upper intake manifold.
13. Install spark plugs, then connect ignition wires to spark plugs.
14. On lefthand cylinder head, proceed as follows;
a. Install oil filler cap.
b. Install generator/power steering pump mounting bracket, then generator.
c. Install accessory drive belt tensioner.
d. Install power steering pump and support bracket, then tighten to specifications.
15. On righthand cylinder head, proceed as follows:
a. Install positive crankcase ventilation valve.
b. Install A/C compressor mounting and supporting brackets, then compressor.
16. Install drive belt.
17. Connect battery ground cable.
18. Install air cleaner outlet tube as follows:
a. Install outlet tube, then connect tube to mass airflow sensor.
b. Connect outlet tube to throttle body, then tighten air cleaner tube clamps on outlet tube.
c. Connect crankcase ventilation tube to air cleaner outlet tube, then wire harness to intake air temperature sensor.
19. Fill engine cooling system with specified coolant.

NOTE: This engine has aluminum cylinder heads and requires a special corrosion inhibited coolant formulation to avoid cooling system damage.

20. Start engine and check for coolant, fuel and oil leaks.