Abstract
In order to meet environmental regulations and to satisfy customer needs, YANMAR has developed the EUP (Electronic Unit Pump) system for medium speed four-stroke diesel engines, with service tools to facilitate maintenance. This system improves fuel consumption at partial load and lowers smoke at low load by controlling fuel injection timing and fuel injection quantity depending on the engine speed and load. With regards to safety, this system assures sufficient reliability through the duplication of the main electronic parts. In October 2009, this system has been released to market as a marine propulsion engine for a cement carrier. At present, this EUP system has been operating without any trouble for more than half a year. This paper presents the outline of our new system.
