Parts for your 1990 Mitsubishi Pajero-Radiator hose

1990 Mitsubishi Pajero Radiator Hose — Purpose, Care, and When to Replace

Yes, a radiator hose is absolutely used on the 1990 Mitsubishi Pajero. Technical sources that call this out include the Mitsubishi Pajero Factory Service Manual (1989–1991, Cooling System section), the Mitsubishi ASA/CAPS parts catalogue for the L040/V20 chassis, plus aftermarket catalogues from Gates and Dayco that list both upper and lower radiator hoses for the 4D56 2.5 turbo-diesel and 6G72 3.0 V6 engines. The Haynes workshop manual for Pajero/Montero of the same era also details hose inspection and replacement. So if the old Pajero’s cooling system is on the list for a spruce-up, radiator hoses are very much part of the picture.

On this model, the radiator hoses do the simple but crucial job of moving coolant between the engine and the radiator. The upper hose carries hot coolant out of the engine to the radiator, and the lower returns cooled fluid back in. Without healthy hoses, the engine can overheat under the bonnet quicker than one would expect, especially on a warm Aussie or Kiwi afternoon or when towing the boat.

As part of regular servicing, it’s smart to inspect the hoses every oil change and replace them on age or condition rather than waiting for a blowout. Rubber hardens, softens, or cracks over time. For most Pajeros of this era, a practical rule is replacement every 4–6 years or around 80,000–100,000 kilometres, whichever comes first.

• Look for soft spots, swelling, cracking, glazing, or oil contamination.
• Check for crusty deposits at hose ends that hint at slow leaks.
• Squeeze-test when the engine is cold, a hose that feels mushy or overly hard is due.
• Inspect clamps, upgrade tired worm drives to quality constant-tension or EFI-style clamps.

When replacing, choose moulded hoses that match the engine (4D56 or 6G72) and the correct shape. It’s a good time to swap the thermostat and radiator cap if they’re old, and to flush the system. Use the correct ethylene glycol coolant at the proper mix with demineralised water. After refitting, bleed out air, bring the engine to temperature with the heater on, and recheck levels. A quick spanner check on clamp torque after a day or two of driving never goes astray.

1. Inspect hoses at every service.
2. Replace at 4–6 years/80–100k km or on any visible wear.
3. Use proper coolant and bleed the system thoroughly.

Look after the hoses and the 1990 Pajero keeps its cool, whether it’s crawling bush tracks or cruising the motorway.

Popular questions about 1990 Mitsubishi Pajero radiator hoses

How often should the radiator hoses be replaced on a 1990 Pajero?
They should be inspected at every service and typically replaced every 4–6 years or 80,000–100,000 kilometres. If there’s cracking, swelling, softness, or leaks, replace them sooner. Age and heat cycles matter more than mileage alone on these older rigs.

What coolant should be used after changing the hoses?
Use a quality ethylene glycol-based coolant mixed with demineralised water to the correct ratio (often around 50/50, or as specified on the coolant label). Avoid mixing incompatible coolant types. After refilling, bleed air properly and recheck the level after the first drive.

Can the Pajero be driven with a small hose leak?
It’s risky. Even a small leak can escalate quickly, leading to overheating and engine damage. If a leak is spotted, top up coolant only to move the vehicle safely off the road and sort a proper repair. Temporary patches are just that—temporary.