Cylinder Head Assembly: Service and Repair

REMOVAL AND INSTALLATION

Removal Service Points 4G6 Engine
[A] Radiator Upper Hose/Radiator Lower Hose Disconnection





Place mating marks on the radiator hose and the hose clamp, and then disconnect the radiator hose.

[B] Cylinder Head Bolt Removal





Using the special tool, loosen the bolts in the order shown in the illustration (in 2 or 3 stages), and then remove the cylinder head assembly.

Installation Service Points
]A[ Cylinder Head Gasket Installation
1. Wipe off all oil and grease from the gasket mounting surface.





2. Install the gasket to the cylinder block with the identification mark facing upwards.

]B[ Cylinder Head Bolt Installation





1. When installing the cylinder head bolts, the length below the head of the bolts should be within the limit. If it is outside the limit, replace the bolts.
Limit (A): 99.4 mm (3.91 inch)
2. Apply engine oil to the bolt thread and the washer.











3. Tighten the bolts by the following procedure.

CAUTION:
1. Always make a tightening angle just 90°. If it is less than 90°, the head bolt will be loosened.
2. If it is more than 90°, remove the head bolt and repeat the procedure from step 1.

]C[ O-Ring Installation





Insert the O-ring to the water inlet pipe, and coat the outer inside diameter of the O-ring with water or engine coolant.

CAUTION: Do not let engine oil or other greases contact with the O-ring.

]D[ Thermostat Case Assembly Installation





1. Loosen the water inlet pipe bolt shown in the illustration.





2. Apply specified sealant to the thermostat case assembly in the places shown in the illustration.
Specified sealant: MITSUBISHI GENUINE PART MD970389 or equivalent
3. Apply a small amount of water to the O-ring of the water inlet pipe, and then press the thermostat case assembly into the water inlet pipe.
4. Tighten the thermostat case assembly mounting bolts.
5. Tighten the water inlet pipe bolts.

]E[ Radiator Lower Hose/Radiator Upper Hose Connection





1. Insert each hose as far as the projection of the water outlet fitting or water inlet fitting.





2. Align the mating marks on the radiator hose and hose clamp, and then connect the radiator hose.

]F[ High-Pressure Fuel Hose Connection
When connecting the high-pressure fuel hose to the fuel rail, apply a small amount of clean engine oil to the hose union and then insert, being careful not to damage the O-ring.

CAUTION: Do not let engine oil get into the fuel rail.