Cylinder Head Assembly: Service and Repair

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:

Fig. 7 Installing brass plug into cylinder head:

1. Clean inside edge of plug hole, Fig. 7, with a wire brush and suitable solvent.
2. Apply suitable sealant to sides of brass plug and hole.
3. Install plug slowly and squarely using an 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 [ERROR-1] 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.

Fig. 8 Cylinder head bolt tightening sequence:

REMOVAL/INSTALLATION
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.
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. Tighten cylinder head bolts in 3 steps, using sequence shown in Fig. 8. Refer to TIGHTENING SPECIFICATIONS under SPECIFICATIONS chart for torque specifications.