Cylinder Head Assembly: Service and Repair

Fig. 12 Installing brass plug into cylinder head:

External coolant loss from the rear lower corner of the left cylinder head and front lower corner of the right cylinder head is the result of a sealing condition around the core clean-out hole in the cylinder head. This condition can be corrected by installing a brass plug kit (part No. 14077197), consisting of two brass plugs and one driver. To install plugs, remove cylinder head as outlined below, then proceed as follows:
1. Clean inside edge of plug hole, Fig. 12, with a wire brush and suitable solvent.
2. Apply suitable sealant to sides of brass plug and hole.
3. Install plug slowly and squarely usingan arbor press and plug driver, until plug is flush with head surface. If the plug deforms or pulls away from side of hole, lightly tap sides of plug to move back into contact with side of hole while sealant is still wet.
4. Remove all old sealant from cylinder head bolt holes in block using an M12 1.75 tap.
5. Clean block mating surfaces and remove any sheared brass or excessive sealant from cylinder head.
6. Install cylinder head as outlined below.


EXC. VAN
1. Remove injection lines, then the intake manifold and rocker arm covers.
2. Drain coolant, remove dipstick tube and disconnect ground wire at cowl.
3. Raise vehicle, disconnect exhaust pipe from manifold, and lower vehicle.
4. Remove A/C compressor (if equipped).
5. Remove generator and disconnect glow plug wires. Remove rocker arm assemblies and pushrods. Mark rocker arms and pushrods so they can be reinstalled in same location.
6. Disconnect radiator, bypass, heater hoses and ground strap.
7. Remove thermostat housing/crossover at cylinder head.
8. Remove cylinder head bolts and cylinder head. Whenever removing a cylinder head on 1982---83 models, the original head bolts should be discarded and new bolts (part No. 14077193) installed. These new type bolts are standard equipment on 1984 and later production engines.

Fig. 13 Cylinder head bolt tightening sequence:

9. Reverse procedure to install, noting the following:
a. Position cylinder head gasket over dowel pins. Do not use any sealer on cylinder head gasket, as sealer is ``printed'' onto gaskets during manufacture, and any additional sealer will increase the possibility of leakage.
b. Coat cylinder head bolts with sealing compound 1052080, or equivalent.
c. Install left rear cylinder head bolt through bolt hole and carefully guide cylinder head onto block.
d. Torque cylinder head bolts in 3 steps, using torque sequence shown in Fig. 13.

1982-83 torque to 88 ft.lbs. (120 Nm) retorque to 103 ft.lbs (140 Nm)
1984-87 torque to 20 ft.lbs. (25 Nm) retorque to 50 ft.lbs. (65 Nm) plus an additional 1/4 turn