Main Engine 4-Stroke · Main Engines (4-Stroke)
The 12AYM-WET is a 12-cylinder V-type, vertical, water-cooled 4-cycle marine diesel engine with 155x180 mm bore/stroke and 40.76 L displacement, developed as the successor to Yanmar's 12LA/16LA series. It meets IMO Tier II emissions using an internal EGR system and mechanical engine control, without added external EGR hardware. Two duty ratings are offered from the same block: M-rating 1220 kW/1900 rpm for intermittent duty and H-rating 1140 kW/1840 rpm, matched to an MGN924VY marine gearbox.
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