New Holland 667TA/EBF, Repair Manual

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2-43
87519804 NA Issued 11-06 Bur
CHAPTER 2 - 667TA ENGINE OVERHAUL
ENGINE REPAIR MANUAL
MECHANICAL SUPPLY PUMP- NORMAL OPERATING CONDITION
BS06K057
Figure 2-52
The charge gear pump, installed on the rear of the
high pressure pump, draws fuel from the tank
through the pre-filter and sends it through the main
fuel filter to the high pressure pump. The feed pump is driven by the high pressure pump
shaft.
In normal operating conditions the flow in the feed
pump enters port (A), flows around the outside of the
gears and out through port (B).
MECHANICAL SUPPLY PUMP- OUTLET OVERPRESSURE CONDITION
BS06K058
Figure 2-53
Pressure safety valve (1) opens when pump outlet
pressure (B), is excessive due to filter restriction or
charge pressure regulator malfunction. The pressure
of the fuel would then overcome the force exerted by spring (1) allowing fuel to flow to the pump inlet
through passage (2).
1. PRESSURE SAFETY VALVE A. FUEL INLET FROM TANK
2. PRIMING BY-PASS VALVE IN CLOSED POSITION B. FUEL OUTLET TO FILTER
2
1
B
A
1. PRESSURE SAFETY VALVE A. FUEL INLET FROM TANK
2. BY-PASS PORT B. FUEL OUTLET TO FILTER
2
1
B
A