New Holland CX720 Repair Manual page 1857

1 Hydraulic activator
3 Strap
Overflow Valve Assembly
The supply pump has a capacity of about twice that of the requirements of the high-pressure pumping elements. This
excess flow provides cooling and lubrication for the injection pump. Flow from the supply pump travels through the
filter element and then to the fuel gallery of injection pump, where it is available to fill the pumping elements. The
fuel must be pressurized in order to properly fill the pumping elements. The job of the overflow valve which is housed
within the body of the banjo bolt (1) is to maintain a pressure of approximately 1.5 bar (22 lbf/in2) in the fuel gallery.
Once that pressure is reached, the overflow valve opens and allows the excess fuel to return to the tank.
High-Pressure Pumping Elements
The high-pressure pumping elements, one for each engine cylinder, supply fuel at a pressure of approximately 240
bar (3500 lbf/in2) to the injectors. The pumping elements must provide the fuel in a precisely measured amount at
the proper time.
Operation of the individual element is as follows:
POWER PRODUCTION - FUEL AND INJECTION SYSTEM
5
70-150-2207
2 Bell crank
6
BSD1883B
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