Mercedes-Benz OM601 / OM602 / OM662
Inline · naturally aspirated · diesel · 1983–present
Also known as: om601, om602, om603, om662, om661, 2.9 five-cylinder diesel, ssangyong xdi
Mercedes' indirect-injection diesels of the 1980s — the four-cylinder OM601, five-cylinder OM602 and six-cylinder OM603 — in the W124 and W201, and licence-built into the SsangYong Musso, Korando and Rexton as the OM661 and OM662.
⚑ That Korean afterlife is why this page exists. SsangYong went on building these long after Mercedes stopped, so a 2000s Korean SUV can carry a 1980s German diesel — and Mercedes parts and Mercedes diagnostic material apply directly, which almost nothing else about those vehicles does. It is the same story as mercedes-m104, which is the petrol six in the same cars.
They are mechanically injected and famously durable. No rail, no filter, nothing to regenerate, and a reputation for very high mileage that is genuinely earned rather than nostalgic.
Their recurring items are old-diesel wear: glow plugs and their relay, an injection pump whose timing drifts with the chain, and injector nozzles that carbon up and knock at idle. The OM60x family is chain-driven, which removes the belt anxiety that defines most diesels of the era.
The wiring harness caution on mercedes-m104 applies here too on the Mercedes-built cars of the early 1990s: biodegradable insulation that crumbles off the loom.
Cars fitted with this engine
2 generations, across 1 make. From the authored catalogue — an absent car means the catalogue has not reached it, not that the engine was never fitted.
Information, not instruction
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