The second answer from Cummins wins.
It looks like fuel supply valve for a THERMOSTART or flame starting system, lines go to two intake heaters. Power to valve opens and supplies diesel to two intake heaters that have fuel lines and a heater element inside that ignites the diesel that drips from heater to preheat the intakes.
Variation of this system is used on many Perkins, Yanmar and other engines sometimes you will find a small reservoir above the engine that is topped off by fuel return line from injection pump going to fuel tank.
BERU information
http://www.beru.com/bw/products/diesel-cold-start-technology/cold-start-aids-for-commercial-vehicles
David
