ENGINE AR-PRIMARY 3636900 - Caterpillar

Illustration 1 g02023390
(1) Fuel temperature sensor (2) Fuel sampling port (3) Fuel pressure sensor (4) Secondary fuel filter baseDo not use the fuel sampling port (2) for measuring the pressure. Follow the steps below.
Table 4
Troubleshooting Test Steps    Values    Results    
2. Check the Fuel Pressure Sensor
A. Record the fuel pressure from Cat ET. Record the data in Table 5.
B. Remove the fuel pressure sensor (3) .
C. Install an 8T-7860 Connector into the port of the pressure sensor (3) .
D. Install the 110-6349 Fitting as onto the 8T-7860 Connector .
E. Install a 8T-0855 Pressure Gauge onto a 6V-3990 Coupler .
F. Install the 6V-3990 Coupler onto the 110-6349 Fitting as .
After the pressure sensor is removed, a code for low fuel pressure will become active. Reset all active codes and clear all logged codes by cycling the keyswitch to the Off position, after the sensor is reinstalled.
G. Record the fuel pressure on the pressure gauge. Record the data in Table 5.    
Fuel pressure
   
Result: The gauge value of the fuel pressure is within 137 kPa (20 psi) of the fuel pressure reading shown in ET.
Proceed to Test Step 3.
Result: The gauge value of the fuel pressure is not within
137 kPa (20 psi) of the fuel pressure reading shown in ET.
Replace the pressure sensor. Reset all active codes and clear all logged codes by cycling the keyswitch to the Off position. Verify that the problem has been resolved.
If the problem is not resolved, proceed to Test Step 3.
   
Table 5
Engine RPM     Fuel pressure from Cat ET     Fuel pressure from the mechanical gauge    
800            
1800            
Illustration 2 g02023433
Fuel supply lines
Illustration 3 g02024502
Return fuel line
Table 6
Troubleshooting Test Steps    Values    Results    
3. Inspect the Fuel Supply Lines
A. Visually inspect the fuel lines between the primary filter base and the inlet to the cylinder head. 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.
   
Restrictions, pinching, and swelling
   
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. Reset all active codes and clear all logged codes by cycling the keyswitch to the Off position. Verify that the problem has been resolved.
If the problem is not resolved, proceed to Test Step 4.
   
Illustration 4 g02024508
(5) Return fuel pressure regulator
Table 7
Troubleshooting Test Steps    Values    Results    
4. Replace the Return Fuel Pressure Regulator
A. Replace the fuel pressure regulator.
   
Fuel pressure regulator
   
Result: The regulator was replaced. Reset all active codes and clear all logged codes by cycling the keyswitch to the Off position. 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 8
Troubleshooting Test Steps    Values    Results    
5. Inspect the Relief Valve for