The OM615.940 Power Plants were the successor to the outgoing OM621 units. They were used in the W123 models from 1976 to 1979 in the 55hp guise with an 87mm bore and 83.6mm stroke. And then a 60 hp unit replaced it in 1979 through to 1985. The engines were as you can imagine no Autobahn cruisers but became the staple model of the taxi ranks across Europe and most of Africa. The majority of which clocked up and or still are clocking up millions of kilometre's. Not hugely popular in the UK they do have a firm following