MOUNTING AS 8W6598 - Caterpillar

System Operation Description:The following lists the probable causes of low fuel pressure:
Fuel
Fuel tank
Fuel filters
Pressure relief valve for the fuel transfer pump
Fuel pressure sensor
Fuel pressure regulator
Return check valve
Fuel linesUse this procedure in order to troubleshoot a low fuel pressure. Use this procedure if one of the following event codes is active. Access the engine monitoring system on Caterpillar Electronic Technician (ET) in order to view the current trip points for these codes. Refer to Troubleshooting, "Engine Monitoring Parameters" for information about engine events.
Table 1
Engine Event
J1939 Code and Description Conditions that Generate the Code System Response
5580-17 Engine Filtered Fuel Delivery Pressure (After Secondary Filter Gauge): Low - least severity (1) The fuel pressure has dropped below trip point for the specified delay time. The code is logged.
5580-18 Engine Filtered Fuel Delivery Pressure (After Secondary Filter Gauge): Low - moderate severity (2) Test Step 1. Determine the Code
Connect Cat ET to the service tool connector. Refer to Troubleshooting, "Electronic Service Tools", if necessary.
Determine if a diagnostic trouble code is present. Results:
Active 5580 Code - Proceed to Test Step 2.
Other Active Code - Repair: Troubleshoot the code. Refer to the proper troubleshooting procedure. Low fuel pressures may cause high fuel temperatures. Troubleshoot a code for low fuel pressure before troubleshooting a code for high fuel temperature.STOPTest Step 2. Check the Fuel Level in the Tank
Remove the fuel tank cap from the fuel tank. Check the vent port that is in the cap for debris. Clear any restrictions with compressed air.
Visually inspect the fuel level in the fuel tank. Ensure that the fuel tank contains enough fuel in order to operate the engine.
Ensure that the fuel supply valve (if equipped) is in the full OPEN position. Results:
The fuel level is OK. - Proceed to Test Step 3.
The fuel level is not OK. - Repair: Fill the tank. Verify that the problem has been resolved. If the problem is not resolved, proceed to Test Step 3.Test Step 3. Inspect the Fuel System for LeaksPerform a visual inspection of the fuel system. Verify that there are no fuel leaks. Inspect the fuel lines from the fuel transfer pump to the secondary fuel filter base for restrictions.Note: Cold weather adversely affects the characteristics of the fuel. Refer to the engines Operation and Maintenance Manual for information on improving the characteristics of the fuel during cold-weather operation.Results:
No leaks were found. - Proceed to Test Step 4.
Leaks were found in the fuel system. - Repair: Repair the leaks. Verify that the problem is resolved. If the problem is not resolved, proceed to Test Step 4.Test Step 4. Compare the Status of Fuel Pressure in Cat ET to a Mechanical Gauge
Table 2
Required Tooling
Quantity Part Number
1 8T-7860 Connector
1 110-6349 Fitting As
1 8T-0855 Pressure Gauge
1 6V-3990 Coupler
Illustration 1 g02051497
Secondary fuel filter mounting
(1) Fuel temperature sensor
(2) Fuel filter differential pressure sensor
(3) Fuel pressure sensor (filtered fuel pressure) Note: Do not use the sampling port for measuring the fuel pressure.
Remove fuel pressure sensor (3).
Install a 8T-7860 Connector into the