Attachment III - Technical Information
FUEL CROSS FLOW WARRANTY EXTENSIONAFFECTED VEHICLES:
ALL 1990, 1991, 1992 AND 1993 MODEL YEAR F-SERIES VEHICLES EQUIPPED WITH 4.9, 5.0, 5.8 OR 7.5 LITER ENGINES AND DUAL FUEL TANKS
TABLE OF CONTENTS
FLOWCHART
SERVICE PROCEDURE
FUEL PRESSURE REGULATOR REPLACEMENT
EXTERNAL CHECK VALVE INSTALLATION AND RETURN LINE INSPECTION - REAR TANK (NON-CHASSIS CAB VEHICLES)
EXTERNAL CHECK VALVE INSTALLATION AND RETURN LINE
INSPECTION - FRONT TANK (ALL VEHICLES)
FUEL DELIVERY MODULE REPLACEMENT AND RETURN LINE INSPECTION - REAR TANK (CHASSIS CAB VEHICLES)
NOTE:
Check OASIS to see if either Safety Recall 00S57 or 93S68 is open. If either recall is open, do not continue with this procedure. Instead, perform the appropriate safety recall and return vehicle to the owner.
SERVICE PROCEDURE
1. Attach an EFI/CFI fuel pressure gauge to the Schrader valve on the engine fuel rail.
2. WARNING:
FUEL IN THE FUEL SYSTEM REMAINS UNDER HIGH PRESSURE, EVEN WHEN THE ENGINE IS NOT RUNNING. BEFORE SERVICING OR DISCONNECTING ANY OF THE FUEL LINES OR FUEL SYSTEM COMPONENTS, THE FUEL SYSTEM PRESSURE MUST BE RELIEVED TO PREVENT ACCIDENTAL SPRAYING OF FUEL, CAUSING PERSONAL INJURY OR A FIRE HAZARD.
Start the engine and record the fuel pressure reading. Turn the ignition key to the OFF position. Then relieve the fuel system pressure by slowly opening the manual valve on the fuel pressure gauge. Remove the gauge from the fuel rail.
ALL EXCEPT CHASSIS CAB
6-CYLINDER ENGINES
^ If the fuel pressure is 55 PSI or less, perform all of the following:
^ External Check Valve Installation And Return Line Inspection - Rear Tank.
^ External Check Valve Installation And Return Line Inspection - Front Tank.
^ If the fuel pressure exceeds 55 PSI, perform all of the following:
^ Fuel Pressure Regulator Replacement.
^ External Check Valve Installation And Return Line Inspection - Rear Tank.
^ External Check Valve Installation And Return Line Inspection - Front Tank.
8-CYLINDER ENGINES
^ If the fuel pressure is 39 PSI or less, perform all of the following:
^ External Check Valve Installation And Return Line Inspection - Rear Tank.
^ External Check Valve Installation And Return Line Inspection - Front Tank.
^ If the fuel pressure exceeds 39 PSI, perform all of the following:
^ Fuel Pressure Regulator Replacement.
^ External Check Valve Installation And Return Line Inspection - Rear Tank.
^ External Check Valve Installation And Return Line Inspection - Front Tank.
CHASSIS CAB
6-CYLINDER ENGINES
^ If the fuel pressure is 55 PSI or less, perform all of the following:
^ Fuel Delivery Module Installation And Return Line Inspection - Rear Tank.
^ External Check Valve Installation And Return Line Inspection - Front Tank.
^ If the fuel pressure exceeds 55 PSI, perform all of the following:
^ Fuel Pressure Regulator Replacement.
^ Fuel Delivery Module Installation And Return Line Inspection - Rear Tank. External Check Valve Installation And Return Line Inspection - Front Tank.
8-CYLINDER ENGINES
^ If the fuel pressure is 39 PSI or less, perform all of the following:
^ Fuel Delivery Module Installation And Return Line Inspection - Rear Tank.
^ External Check Valve Installation And Return Line Inspection - Front Tank.
^ If the fuel pressure exceeds 39 PSI, perform all of the following:
^ Fuel Pressure Regulator Replacement.
^ Fuel Delivery Module Installation And Return Line Inspection - Rear Tank.
^ External Check Valve Installation And Return Line Inspection - Front Tank.
FUEL PRESSURE REGULATOR REPLACEMENT
NOTE:
Perform only if fuel pressure exceeds levels specified earlier in this procedure.
1. Install a memory saver, then disconnect the battery negative cable.
2. Disconnect the vacuum line from the fuel pressure regulator, which is located on the fuel rail.
3. Remove the retaining screws from the fuel pressure regulator.
4. Remove and discard the fuel pressure regulator, gasket and 0-ring seal from the fuel rail manifold.
5. Lubricate the new fuel pressure regulator 0-ring with light oil (10W30 oil WSE-M2C903-A2 or equivalent). Install the new o-ring and the new gasket on the new regulator.
6. Position the new fuel pressure regulator with 0-ring and gasket onto the fuel rail and install the retaining screws. Tighten the screws to 4 Nm (35 lb-in).
7. Connect the vacuum line to the new fuel pressure regulator.
EXTERNAL CHECK VALVE INSTALLATION AND RETURN LINE INSPECTION - REAR TANK (NON-CHASSIS CAB VEHICLES)
1. Install a memory saver, then disconnect the battery negative cable.
2. Drain the rear fuel tank, using Rotunda Fuel Storage Tanker 034-00002, 034-00014 or equivalent.
3. Raise the vehicle on a hoist.
4. Position the spare tire out of the way.
5. Loosen the hose clamp at the fuel filler hose connection to the rear fuel tank.
6. Position a safety stand under the rear fuel tank.
7. Remove the fuel tank support straps.
8. Access the fuel delivery module (FDM) at the top of the tank by lowering the tank while guiding the fuel filler hose from the tank.
9. NOTE: For vehicles equipped with stainless steel braided flex lines, proceed to the next step. Inspect the nylon fuel return lines for kinking.
^ If the nylon fuel return line is not kinked or the vehicle is equipped with stainless steel braided flex lines, proceed to the next step.
^ If the nylon return line is kinked, repair the line as necessary using Rotunda Tool 134-000001 (Plastic Fuel Line Fitting Connector Tool), before continuing this procedure.
10. NOTE: Remove and discard the black hairpin clip on 1990 and 1991 model year vehicles. A new clip will be used when reconnecting the fuel supply line.
Disconnect the fuel supply line at the FDM. See Figure 1.
11. If equipped, remove and discard the old external check valve.
12. Install the external check valve to the supply tube of the FDM. Install the fuel line clip onto the external check valve. See Figure 1.
13. Connect the fuel supply line to the external check valve. Install a new black hairpin clip on 1990 and 1991 model year vehicles. See Figure 1.
14. Raise the rear fuel tank back into position while guiding the fuel filler hose onto the fuel tank.
15. Install the fuel tank straps. Tighten bolts to 38 Nm (28 lb-ft).
16. Tighten the fuel filler hose clamp to 4 Nm (35 lb-in).
17. Remove the safety stand.
18. Reposition the spare tire.
19. Lower the vehicle.
EXTERNAL CHECK VALVE INSTALLATION AND RETURN LINE INSPECTION - FRONT TANK (ALL VEHICLES)
1. Drain the front fuel tank, using Rotunda Fuel Storage Tanker 034-00002, 034-00014 or equivalent.
2. Raise the vehicle on a hoist.
3. Remove the skid plate if equipped.
4. Loosen the hose clamp at the fuel filler hose connection to the front tank.
5. Position a safety stand under the fuel tank.
6. Remove the fuel tank support strap bolts.
7. Access the FDM at the top of the tank by lowering the tank while guiding the fuel filler hose from the tank.
8. NOTE: For vehicles equipped with stainless steel braided flex lines, proceed to the next step. Inspect the nylon fuel return line for kinking.
^ If the nylon fuel return line is not kinked or the vehicle is equipped with stainless steel braided flex lines, proceed to the next step.
^ If the nylon return line is kinked, repair the line as necessary using Rotunda Tool 134-000001 (Plastic Fuel Line Fitting Connector Tool), before continuing this procedure.
9. NOTE: Remove and discard the black hairpin clip on 1990 and 1991 model year vehicles. A new clip will be used when reconnecting the fuel supply line.
Disconnect the fuel supply line at the fuel delivery module. See Figure 2.
10. If equipped, remove and discard the old external check valve.
11. Install the external check valve to the supply tube of the fuel delivery module. Install the fuel line clip onto the external check valve. See Figure 2.
12. Connect the fuel supply line to the external check valve. Install a new black hairpin clip on 1990 and 1991 model year vehicles.
13. Reinstall the skid plate if removed.
14. Lower the vehicle.
15. Fill the fuel tanks.
16. Connect the battery negative cable, then remove the memory saver.
17. Without starting the engine, turn the ignition key on and off several times to pressurize the fuel system and check for leaks.
FUEL DELIVERY MODULE REPLACEMENT AND RETURN LINE INSPECTION - REAR TANK (CHASSIS CAB VEHICLES)
1. Install a memory saver, then disconnect the battery negative cable.
2. Drain the rear fuel tank, using Rotunda Fuel Storage Tanker 034-00002, 034-00014 or equivalent.
3. Raise the vehicle on a hoist.
4. Position the spare tire out of the way.
5. Loosen the hose clamp at the fuel filler hose connection to the rear fuel tank.
6. Position a safety stand under the rear fuel tank.
7. Remove the fuel tank support skid plate bolts.
8. Access the fuel delivery module (FDM) at the top of the tank by lowering the tank while guiding the fuel filler hose from the tank.
9. NOTE: Remove and discard the black hairpin clip. A new clip will be used when reconnecting the fuel supply line.
Disconnect the fuel supply line, fuel return line and the electrical connector (not shown) from the FDM See Figure 3.
10. Disconnect the vapor line from the fuel tank. See Figure 3.
11. Lower the fuel tank while guiding the fuel filler hose out of the tank.
12. NOTE: For vehicles equipped with stainless steel braided flex lines, proceed to the next step. Inspect the nylon fuel return line for kinking.
^ If the nylon fuel return line is not kinked or the vehicle is equipped with stainless steel braided flex lines, proceed to the next step.
^ If the nylon return line is kinked, repair the line as necessary, using Rotunda Tool 134-000001 (Plastic Fuel Line Fitting Connector Tool) before continuing this procedure.
13. Clean any dirt from the top of the tank around the FDM.
14. Remove the locking ring from the FDM.
15. Remove the FDM, then remove and discard the gasket.
16. Clean the FDM mounting flange on the fuel tank, then install a new gasket onto the flange.
17. Install the new FDM, then install the locking ring. Tighten the locking ring to 62 Nm (46 lb-ft).
18. Raise the tank up into the vehicle, leaving enough mom to make the connections on the top of the tank.
19. Connect the vapor line to the fuel tank.
20. Connect the fuel supply, fuel return and electrical connector to the FDM. Install a new black hairpin clip on the fuel supply line connection.
21. Raise the rear fuel tank into position while guiding the fuel filler hose into the tank.
22. Install the fuel tank support skid plate bolts. Tighten bolts 44 Nm (32 lb-ft).
23. Tighten the fuel filler hose clamp to 4 Nm (35 lb-in).
24. Remove the safety stand.
25. Reposition the spare tire.
26. Lower the vehicle.