Parts for your 1991 Mitsubishi Pajero-Head gasket

1991 Mitsubishi Pajero head gasket — what it does and how to look after it

Technical sources confirm the 1991 Mitsubishi Pajero uses a cylinder head gasket, so the part is absolutely relevant to this model. References include: Mitsubishi Pajero/Montero/Shogun Workshop Manual (1991, Engine Mechanical – Cylinder Head), Mitsubishi Motors 4D56 Diesel Engine Service Manual (head gasket thickness and torque procedures), Mitsubishi 6G72 V6 Engine Manual (cylinder head and gasket replacement), and common aftermarket manuals such as Haynes and Gregory’s for 1983–1997 Pajero models. These manuals detail the gasket’s function, torque sequences, and replacement specs for engines fitted to 1991 Pajeros, including the 2.5L 4D56 diesel and 3.0L 6G72 V6.

On their 1991 Pajero, the head gasket seals the join between the engine block and the cylinder head. It keeps combustion pressure in the cylinders while keeping oil and coolant in their own passages. When it’s healthy, the engine runs crisp, stays cool, and doesn’t drink fluids. When it fails, owners can see overheating, rough running, and cross-contamination of oil and coolant.

It’s not a routine “replace by kilometres” item — it’s replaced if it fails or when the head is off for other work. That said, smart servicing helps it live a long life:

• Maintain the cooling system: fresh coolant per the manual, a healthy radiator cap, clean radiator, working fans and thermostat. Overheating is the head gasket’s worst enemy.
• Use proper torque and sequence: if the head ever comes off, follow the factory tightening order and angle stages. On 4D56 and 6G72 engines, use new head bolts as specified.
• Check the head and block: have the cylinder head pressure-tested and skimmed if needed