Cylinder Head Assembly: Service and Repair
REMOVAL1. Disconnect battery ground cable.
2. Remove cap from expansion tank.
3. Remove splash guard.
Radiator Drain:
4. Drain coolant through coolant drain plug on radiator.
5. Remove drive belt, then the drive belt cover.
6. Turn engine to TDC of cylinder No. 1.
TDC Mark:
Crankshaft Timing Marks:
7. Remove distributor cap, distributor rotor, and dust cover.
Distributor Rotor:
8. Remove distributor cap mount.
9. Slacken belt tension and pull camshaft belt off of camshaft sprocket, Timing Belt.
10. Loosen two mounting bolts on rear drive belt cover.
Rear Drive Belt Cover Mounting Bolts:
11. Disconnect fuel lines.
Fuel Lines:
12. Remove plastic cover from fuel collection tube, pull off wire plugs on fuel injectors, and position wiring harness out of way.
Cam Housing:
13. Unscrew aluminum plugs, coolant line, and bolts with attached washers, then remove camshaft housing from cylinder head.
NOTE: Ensure that hydraulic valve tappets do not fall out and are not mixed up.
14. Remove air cleaner assembly.
Intake Brace:
15. Remove intake brace attaching bolt.
16. Remove intake manifold by dismantling holder on oil dipstick tube, hose on brake booster, hose on intake distributor, retaining clamp on accelerator cable, and mounting bolts of intake distributor/cylinder head.
Exhaust Flange:
17. Remove bolts from flange connecting catalytic converter and exhaust manifold.
18. Remove hose clamp from heater regulating valve and the two screws on neck of cooling circuit.
19. Remove cylinder head attaching bolts in a criss-cross fashion from outside to inside, then remove cylinder head.
INSTALLATION
1. Reverse procedure to install, noting the following steps:
CAUTION: When torquing cylinder head stud nuts, never lubricate the studs, only lightly coat the nuts with clean engine oil. The washers must not turn when torquing the cylinder head nuts.
Fig. 1 Cylinder head tightening sequence.:
2. Tightening specifications to torque angle method, tightening is done in three steps:
a. 1st stage 20 Nm (15 ft. lbs.)
b. 2nd stage 90 degrees rotation angle (1/4 turn)
c. 3rd stage 90 degrees rotation angle (1/4 turn)
3. The 12mm high cylinder head nuts might protrude above the studs slightly on engines produced prior to Feb. 1986. In addition, new head nuts must be used at each repair.
4. Torque camshaft housing socket head bolts to 20 Nm (14 ft lb) and aluminum plugs to 40 Nm (29 ft lb).
REMOVAL
NOTE: This information includes information from TSB# 18703, MARCH 1987
1. Disconnect battery ground cable.
2. Remove cap from expansion tank.
3. Remove splash guard.
Radiator Drain:
4. Drain coolant through coolant drain plug on radiator.
5. Remove drive belt, then the drive belt cover.
6. Turn engine to TDC of cylinder No. 1.
TDC Mark:
Crankshaft Timing Marks:
7. Remove distributor cap, distributor rotor, and dust cover.
Distributor Rotor:
8. Remove distributor cap mount.
9. Slacken belt tension and pull camshaft belt off of camshaft sprocket, Timing Belt.
10. Loosen two mounting bolts on rear drive belt cover.
Rear Drive Belt Cover Mounting Bolts:
11. Disconnect fuel lines.
Fuel Lines:
12. Remove plastic cover from fuel collection tube, pull off wire plugs on fuel injectors, and position wiring harness out of way.
Cam Housing:
13. Unscrew aluminum plugs, coolant line, and bolts with attached washers, then remove camshaft housing from cylinder head.
NOTE: Ensure that hydraulic valve tappets do not fall out and are not mixed up.
14. Remove air cleaner assembly.
Intake Brace:
15. Remove intake brace attaching bolt.
16. Remove intake distributor by dismantling holder on oil dipstick tube, hose on brake booster, hose on intake distributor, retaining clamp on accelerator cable, and mounting bolts of intake distributor/cylinder head.
Exhaust Flange:
17. Remove bolts from flange connecting catalytic converter and exhaust manifold.
18. Remove hose clamp from heater regulating valve and the two screws on neck of cooling circuit.
19. Remove cylinder head attaching bolts in a criss-cross fashion from outside to inside, then remove cylinder head.
INSTALLATION
1. Reverse procedure to install, noting the following steps:
CAUTION: When torquing cylinder head stud nuts, never lubricate the studs, only lightly coat the nuts with clean engine oil. The washers must not turn when torquing the cylinder head nuts.
Fig. 1 Cylinder head tightening sequence.:
2. Tightening specifications to torque angle method, tightening is done in three steps:
a. 1st stage 20 Nm (15 ft. lbs.)
b. 2nd stage 60 degrees rotation angle (1/6 turn)
c. 3rd stage 60 degrees rotation angle (1/6 turn)
3. The 12mm high cylinder head nuts might protrude above the studs slightly on engines produced prior to Feb. 1986. In addition, new head nuts must be used at each repair.
4. Torque camshaft housing socket head bolts to 20 Nm (14 ft lb) and aluminum plugs to 40 Nm (29 ft lb).