Parts for your 1987 Mitsubishi Pajero-Oil pump

1987 Mitsubishi Pajero oil pump — what it does and how to look after it

Technical sources confirm the 1987 Mitsubishi Pajero does use an engine oil pump. The Mitsubishi Pajero/Montero Factory Service Manual (1983–1991, Lubrication section), the Mitsubishi engine workshop manuals for the 4G54 (2.6 petrol), 4D55/4D56 (2.3/2.5 turbo‑diesel) and 6G72 (3.0 V6), plus the Haynes Montero 1983–1993 and Gregory’s Pajero 1983–1996 repair manuals all depict a crankshaft‑driven trochoid/gear‑type pump mounted in the front case. So the oil pump is absolutely relevant and serviceable on a 1987 Pajero.

On any 1987 Pajero, the oil pump is the heart of the engine’s lubrication system. Spinning off the crank, it sends pressurised oil through galleries to bearings, cam/rockers, lifters and (on turbo diesels) the turbo. That pressure keeps a film of oil between moving parts, carries away heat, and traps debris in the filter. If pressure drops, bearings can score in seconds — not the sort of outback memory anyone wants.

Day-to-day care is simple: quality oil and filters, on time. For Aussie and Kiwi conditions — towing, beach runs, heat — many owners stick to 5,000–7,500 km oil changes with the grade specified for the engine and climate (commonly 15W‑40 or 10W‑40). Keep an eye on the dash oil light and any factory or aftermarket gauge. A quick mechanical gauge test at service time is cheap insurance, especially on higher‑kilometre trucks.

When symptoms crop up, act early. Typical signs include:

• Oil light flickering at hot idle or lagging after start
• Tappet/lifter rattle that quietens with revs
• Low indicated pressure at cruising rpm
• Front main seal weeping or oil in the timing cover (often serviced with the pump/front case)

Replacement or overhaul varies by engine, but the pump is usually integral with the front cover. That means the timing belt/chain area is opened up, making it a smart “while you’re in there” job during timing belt service on 4D55/4D56 diesels, and a good time to renew the front crank seal and pickup O‑rings. Always inspect the pickup strainer, relief valve and rotor clearances, and prime the pump with assembly lube or petroleum jelly. Prefill the filter and crank with ignition/fuel disabled until pressure registers. Done right, the refreshed pump helps these classic Pajeros rack up plenty more kilometres without drama.

Technical references: Mitsubishi Pajero/Montero Factory Service Manual (1983–1991, Lubrication), Mitsubishi Engine Workshop Manuals (4G54, 4D55/4D56, 6G72), Haynes Montero 1983–1993, Gregory’s Pajero 1983–1996.

Popular questions

Does a 1987 Mitsubishi Pajero have an oil pump?
Yes. All 1987 Pajero engines (2.6 petrol, 2.3/2.5 turbo‑diesel, and early 3.0 V6) run a crank‑driven trochoid/gear‑type oil pump in the front case, as shown in Mitsubishi factory and aftermarket workshop manuals.

What oil pressure should it show?
Figures vary by engine and condition, but a healthy hot idle is typically around 70–100 kPa (10–15 psi) and 300–500 kPa (45–70 psi) by 3,000 rpm. Always verify specs for the exact engine code and test with a mechanical gauge if the dash warning flickers.

Should the oil pump be serviced with the timing belt?
On 4D55/4D56 diesels the pump/front case is accessed with the timing belt off, so it’s a convenient time to inspect clearances, replace the front crank seal, and renew pickup O‑rings. Priming the pump on reassembly is essential.