Usage:
3508 ( 23Z ),
3512 ( 24Z ),
3516 ( 25Z ) Generator Set Engines
A fuel return line has been added to the fuel system. Formerly, only a single line ran between the main fuel tank and the engine. The unused fuel was circulated through a fuel cooler and back to the engine. In certain conditions, this could lead to air being trapped in fuel system which could result in rough starts. It could also lead to overheated fuel when operating in high ambient temperatures. This could result in a loss of power. Now, a fuel return line circulates excess fuel back through the fuel cooler to the main fuel tank. This will help prevent air from being trapped in the fuel system and will also help prevent the fuel temperature from getting too high.
A second fuel/water separator is included with the added fuel return line. It will provide the added separator capacity required because of the increased fuel circulation between the engine and the fuel tank.
These changes are in effect with 3508, 3512, and 3516 Generator Set Engines 23Z3050, 24Z3167, and 25Z1814 respectively.