ELBOW 2N8827 - Caterpillar

Illustration 1 g02041554
(1) Fuel temperature sensor (2) Fuel pressure sensor "A" (3) Fuel pressure sensor "B" (4) Fuel filter base
Table 4
Troubleshooting Test Steps    Values    Results    
2. Check Fuel Pressure Sensor "A"
A. Record the unfiltered fuel pressure from Cat ET. Record the value in Table 6.
B. Remove fuel pressure sensor "A" (2) .
C. Install a 5P-1318 Adapter into the port of the pressure sensor "A" (2) .
D. Install the 123-0783 Fluid Sampling Valve Gp onto the 5P-1318 Adapter.
E. Install a 8T-0855 Pressure Gauge onto a 6V-3990 Coupler.
F. Install the 6V-3990 Coupler onto the 123-0783 Fluid Sampling Valve Gp.
G. Record the fuel pressure from the pressure gauge. Record the pressure in Table 6.    
Pressure sensor    
Result: The gauge value of the fuel pressure is within
69 kPa (10 psi) of the unfiltered fuel pressure reading shown in Cat ET.
Proceed to Test Step 3.
Result: The gauge value of the fuel pressure is not within
69 kPa (10 psi) of the unfiltered fuel pressure reading shown in Cat ET.
Replace the pressure sensor. Verify that the problem has been resolved.
If the problem is not resolved, proceed to Test Step 3.
   
Table 5
Required Tooling for Pressure Sensor "A"    
5P-1318 Adapter    
123-0783 Fluid Sampling Valve Gp    
8T-0855 Pressure Gauge    
6V-3990 Coupler    
Table 6
Engine RPM     Unfiltered fuel pressure from Cat ET     Fuel pressure from the mechanical gauge    
800            
1800            
Illustration 2 g02041759
Fuel supply lines
Illustration 3 g02041781
Fuel return line
Table 7
Troubleshooting Test Steps    Values    Results    
3. Inspect the Fuel Supply and Return Lines
A. Visually inspect the fuel lines between the primary filter base and the inlet to the fuel injection pump. Also, inspect the fuel cooler, if equipped. Inspect the fuel return line from the head to the fuel tank. Inspect the lines for restrictions, pinching, and swelling. Refer to Systems Operation/Testing and Adjusting, "Fuel System - Inspect" for additional information.
   
Inspect lines    
Result: The fuel lines and the cooler (if equipped) are OK.
Proceed to Test Step 4.
Result: The fuel lines and the cooler (if equipped) are not OK.
Make the necessary repairs. Verify that the problem has been resolved.
If the problem is not resolved, proceed to Test Step 4.
   
Illustration 4 g02041814
(5) Return fuel pressure regulator
Table 8
Troubleshooting Test Steps    Values    Results    
4. Replace the Return Fuel Pressure Regulator
A. Replace the fuel pressure regulator.
   
Pressure regulator    
Result: The regulator was replaced. Verify that the problem is resolved.
If the problem is not resolved, proceed to Test Step 5.
   
Illustration 5 g02031818
Typical fuel transfer pump (6) Relief valve
Table 9
Troubleshooting Test Steps    Values    Results    
5. Inspect the Relief Valve for the Fuel Transfer Pump
A. Inspect the relief valve for the transfer pump. The spring must move freely.
   
Transfer pump    
Result: The relief valve is stuck CLOSED.
Replace the fuel transfer pump. Verify that the problem