Parts for your 1986 Mitsubishi Pajero-Radiator

1986 Mitsubishi Pajero Radiator — What it does and how to look after it

A radiator is absolutely fitted to the 1986 Mitsubishi Pajero. Authoritative technical sources — including the Mitsubishi Pajero (L040/L140) Factory Service Manual, the Gregory’s/ Haynes Pajero workshop manuals for 1983–1991 models, and the Mitsubishi ASA parts catalogue — all specify a liquid-cooled system with a crossflow radiator, an engine-driven viscous fan, and (on many A/C-equipped vehicles) an auxiliary electric fan.

On this classic 4x4, the radiator’s job is to shed the engine’s heat so it runs at the sweet spot for power and longevity. Coolant circulates through the block and head, picks up heat, then passes through the radiator core where air flow under the bonnet whisks that heat away. The thermostat regulates flow, the cap maintains pressure, and the overflow bottle catches expansion — all helping to prevent detonation, warped heads, and cooked oil. For both the 2.6-litre 4G54 petrol and the 2.5-litre 4D56 diesel, a healthy radiator is non‑negotiable, especially in Aussie and Kiwi summers or low‑range climbs.

As part of regular servicing, coolant should be replaced every 2 years or around 40–50,000 kilometres. Use a quality ethylene glycol coolant suitable for older Japanese alloys (often the familiar green IAT type) mixed 50/50 with demineralised water. Inspect hoses, clamps, the radiator cap, thermostat, and the viscous fan clutch. Keep the core clean — mud, seeds and bugs can pack the fins after off‑road work. If the gauge wanders, the heater goes cold under load, or there’s a sweet smell and white crust around tanks, it’s time for checks.

• Check coolant level stone cold, weekly.
• Pressure-test the cap and system if you’re chasing leaks.
• Don’t mix coolant types