OM447

Production began in December 1984, and the version that mattered was not the upright one. Rear-engined city buses need their engine flat, so the OM 447h went in on its side beneath the floor of the Mercedes-Benz O 405 — the second generation of the VÖV standard bus, built from 1984 to 2002 and made in roughly 12,000 examples. Ratings ran from 157 kW naturally aspirated to 184 kW turbocharged and intercooled, and operators who wanted natural gas could have the M 447 hG at 150 kW.

The O 405N low-floor and O 405G articulated versions used it too, as did Setra’s S 215 UL and S 315 UL at up to 257 kW, with bodybuilders from Spain to Greece working on the same chassis. In Brazil the OM 447 LA became a truck and coach engine in its own right — the L 1634, the OH 1635 bus chassis — and a generating-set unit long after Europe had moved on. Its European successor, the OM 457, kept the same 128 × 155 mm cylinder and swapped the inline pump for unit pumps.