Cascade Overflow Valve (Cov)

Fig.27 Overflow Value:

Cascade Overflow Valve
The cascade overflow valve is located on the top/rear side of the fuel injection pump (Fig 27)

When the fuel control actuator (FCA) is opened, the maximum amount of fuel is being delivered to the fuel injection pump. Any fuel that does not enter the injection pump is directed to the cascade overflow valve. The cascade valve regulates how much excess fuel is used for lubrication of the injection pump, and is also used to route excess fuel through the drain circuit and back into the fuel tank.