Mercedes-Benz OM617 engine

The Mercedes-Benz OM617 is a straight-five diesel engine sold in vehicles from 1974 to 1991 and a direct development of the four-cylinder OM616, essentially that engine with an extra cylinder. It debuted in 1974 with the W115 and later powered the W123 and the G-Class, at first making 80 PS from a 3.0 litre displacement. Naturally aspirated versions used Bosch MW inline pumps, and the precombustion chamber was revised in August 1978 along with a trim of displacement to 2,998 cc. A turbocharged OM617A followed. The engine is considered one of the most reliable ever produced, with examples reaching over a million kilometres, and was a key reason for the popularity of Mercedes diesels in North America in the 1980s.