Cylinder Head Assembly: Service and Repair

REMOVAL

Fig. 20 Cylinder Head Removal (Part 1 Of 2).:

Fig. 20 Cylinder Head Removal (Part 2 Of 2).:

Remove cylinder head in numbered sequence, Fig. 20, noting the following:
1. Before disconnecting high pressure fuel line, relieve fuel pressure as follows:
a. Disconnect fuel pump harness connector at fuel tank.
b. Start engine and let it run until it stalls, then turn ignition switch to off.
c. Disconnect battery ground cable.
d. Reconnect fuel pump harness connector.
2. Before removing upper radiator hose, mark hose clamp in relation to hose for assembly reference, then drain coolant as follows:
a. Place instrument panel temperature control lever in Hot position.
b. Carefully remove radiator cap.
c. Remove radiator drain plug.
3. Refer to TIMING BELT when removing timing belt.

Fig. 21 Head Bolt Removal Sequence.:

4. Using cylinder head bolt wrench No. MD998051, or MB991654, or equivalent, remove cylinder head bolts in sequence as shown in Fig. 21.

INSTALLATION

Reverse removal procedure to install, noting the following:
1. Install cylinder head gasket as follows:
a. Using a suitable scraper, remove old gasket material from cylinder block, using care not to allow old gasket material to fall into cylinder or passages.
b. Clean head and block surfaces that come in contact with head gasket.
c. Place head gasket on block with identification mark at top front.
NOTE: Do not apply sealant to head gasket.

Fig. 22 Head Bolt Tightening Sequence.:

Without Multi Layer Steel Head Gasket

2. When installing cylinder head, install head bolt washers, then torque head bolts to specifications as follows:
a. Inspect shank length of each bolt before installation. If shank length exceeds 3.91 in, then replace the bolt.
b. Torque bolts to 58 ft.-lbs. in order as shown in Fig.22.
c. Fully loosen bolts in order shown in Fig.21.
d. Torque bolts to 14-15 ft.-lbs. in order shown in Fig.22, then tighten in sequence an additional 180° in 90° increments.

With Multi Layer Steel Head Gasket

Note: The four short bolts are placed in the corners.

Step 1
Torque all center bolts to 34 Nm (25 Ft Lbs), Torque the 4 corner bolt to 27 Nm (20 Ft Lbs)
Step 2
Torque all center bolts to 68 Nm (50 Ft Lbs), Torque the four corner bolts to 47 Nm (35 Ft Lbs),
Step 3
Re-torque all center bolts to 68 Nm (50 Ft Lbs), Re-torque the 4 corner bolts to 47 Nm (35 Ft Lbs).
Step 4
Tighten all bolts in the Specified sequence an additional 90° (1/4 turn).

Fig. 23 Installing Rocker Cover.:

3. When installing semi-circular packing, apply liberal amount of gasket sealant onto circumference of packing.
4. When installing rocker cover, apply gasket sealant to area as shown in Fig. 23.
5. Refer to TIMING BELT when installing timing belt.
6. When installing high pressure fuel line (5), apply small amount of gasoline to hose union. Use care to avoid damaging O-ring.