The BMW M51 is an inline-6 cylinder Diesel engine produced by the Upper Austrian BMW plant in Steyr from July 1991 through February 2000. Its predecessor is the BMW M21; the successor is the BMW M57.
Description
The M51 is a water-cooled and turbocharged inline six-cylinder diesel engine. It is an indirect injection design with fuel supplied by a Bosch VP37 mechanical injection pump. The displacement is 2,497 cc (152.4 cu in) and the compression ratio is 22.0:1.
Some engine variants have an intercooler in addition to the turbocharger; vehicles so equipped can be identified by the designation tds. || <br/> at 1400 rpm || 1994–2001
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| M51D25TÜ UL || <br/> at 4800 rpm || <br/> at 1900 rpm || 1996–1998
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| M51D25TÜ OL || <br/> at 4800 rpm
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