105681-2470 ZEXEL Cross 1056812470

Locations and Methods for Measuring the Pressures of the Low-Pressure Fuel System
Illustration 1 g03325145
Front View of a typical fuel inlet lines group (A) Fuel inlet port (B) Test port for the fuel supply pressure (C) Fuel transfer pump (D) Test port location for system pressureInlet Fuel Pressure to the Transfer Pump (set at rated speed and load)
Install a 6V-3965 Fitting into Port (B) using a 214-7568 O-Ring Seal Note: The inlet pressure to the fuel transfer pump can affect overall system pressure. All filters or water separators before the transfer pump must be new and clean prior to setting the system pressure at the fuel pressure regulator.
Connect the 6V-7830 Pressure Gauge to the fitting installed in the previous step.
Set the engine to rated speed and load. Record the fuel pressure, and refer to the specifications above.Primary and Secondary Fuel Filter Differential Pressure
Primary and secondary fuel filter differential pressures are determined by the pressures from both sides of the fuel filters. This measurement will monitor fuel filter cleanliness and determine when the fuel filters require changing. Filter replacement will vary depending on fuel quality. Fuel quality can change with each shipment of fuel so monitoring the filter differential is necessary to obtain maximum filter life.Too high of a differential can cause air bubbles in the fuel system and if not corrected will lead to poor performance and injector damage. After the measurements are taken, refer to the specification above for the maximum allowable differential pressure.Primary filters or water separators should be properly sized to meet the flow requirements of the engine or engines as well as fuel being returned to the tank. Reference Table 4 for the flow requirements.
Table 4
3600 Engine Fuel Flow    
Engine Model     Rated Speed (rpm)     Fuel Flow to Engine     Fuel Flow from Engine     Fuel Heat Rejection    
3606     1000    
41.5 L/min (11 US gpm)    
32.4 L/min (8.6 US gpm)    
12.5 kW (712 Btu/min)    
900
38 L/min (10 US gpm)    
30.0 L/min (7.9 US gpm)    
11.0 kW (626 Btu/min)    
750
31.5 L/min (8.3 US gpm)    
24.5 L/min (6.5 US gpm)    
10.5 kW (598 Btu/min)    
720
30 L/min (7.9 US gpm)    
23.6 L/min (6.2 US gpm)    
10.0 kW (567 Btu/min)    
3608     1000    
41.5 L/min (11 US gpm)    
30.0 L/min (7.9 US gpm)    
16.7 kW (951 Btu/min)    
900
38 L/min (10 US gpm)    
27.6 L/min (7.3 US gpm)    
14.6 kW (831 Btu/min)    
750
31.5 L/min (8.3 US gpm)    
22.6 L/min (6.0 US gpm)    
14.0 kW (797 Btu/min)    
720
30 L/min (7.9 US gpm)    
21.4 L/min (5.6 US gpm)    
13.3 kW (757 Btu/min)    
3612     1000    
78.5 L/min (20.7 US gpm)    
60.1 L/min (15.9 US gpm)    
25.0 kW (1423 Btu/min)    
900
72 L/min (19 US gpm)    
55.4 L/min (14.6 US gpm)    
22.0 kW (1252 Btu/min)    
750
61.2 L/min (16.2 US gpm)    
47.3