Parts for your 1992 Mitsubishi Pajero-Coolant

1992 Mitsubishi Pajero coolant: what it does and how to look after it

Coolant is absolutely relevant and required on the 1992 Mitsubishi Pajero. Mitsubishi’s Owner’s Manual and Factory Service Manual for early-’90s Pajero models (NH/NJ series) specify a pressurised liquid cooling system using an ethylene glycol-based coolant mixture, and independent workshop guides like Haynes detail the same setup across both petrol V6 and diesel engines.

For this Pajero, coolant (antifreeze) isn’t just about keeping temps in check. It lifts the boiling point, drops the freezing point, and packs corrosion inhibitors to protect alloy heads, cast iron blocks, the radiator, water pump, and heater core. With towing, off‑road low‑speed work, and Aussie and Kiwi summer heat, a healthy cooling system is vital to prevent hot spots, detonation, and head-gasket grief.

Owners should use a high-quality ethylene glycol coolant suitable for mixed metals and aluminium, mixed with demineralised water—typically 50/50 for broad protection. Don’t mix types (green, red, blue) unless explicitly compatible, if switching formulations, do a thorough flush first. Capacity varies by engine, so check the manual or under-bonnet decal if fitted.

A practical service rhythm for an original‑type green coolant is every 2 years or around 40,000 km. Long-life coolants may go longer if they meet Mitsubishi specs, but they still need periodic checks. Between changes, top up only with premix of the same type, and inspect the overflow bottle’s “FULL” mark when cold.

• Inspect hoses, clamps, radiator cap, and the thermostat at each service, replace any perished or soft hoses and a weak cap.
• Flush until runoff is clear, then refill with the correct premix. Run the engine with the heater on hot to purge air, and bleed as per the workshop procedure.
• Use a refractometer or hydrometer to verify concentration, and keep an eye out for rusty colour, oil sheen, sweet smells, or unexplained loss—these need attention.
• After heavy towing or beach work, check for mud or seed build-up in the radiator fins and clean carefully.

A Pajero that runs the right coolant at the right strength, with a sound cap and thermostat, will handle climbs, corrugations, and city traffic without breaking a sweat. It’s simple maintenance that pays off in engine longevity.

Popular questions

What coolant type and mix should a 1992 Pajero use?
Use a quality ethylene glycol‑based coolant suitable for aluminium components, mixed with demineralised water at about 50/50. This gives strong boil-over and freeze protection plus corrosion control. Stick with one chemistry and don’t mix colours unless the manufacturer states they’re compatible.

How often should the coolant be changed?
For conventional green coolant, every 2 years or roughly 40,000 km is a safe bet. If running an approved long‑life coolant, intervals can be longer, but still test the concentration and condition annually and follow the product and Mitsubishi guidance.

How do you bleed air from the system after a flush?
Fill slowly, set the heater to hot, and run the engine with the radiator cap off until the thermostat opens and bubbles stop. Top up, fit a good cap, and bring the overflow bottle to the cold “FULL” mark. Recheck levels after the first proper drive. Use the factory bleed points if your engine variant has them.