Engine - Stalls When Coming to A Stop
Article No.94-5-11
03/09/94
STALLS - 6.9L/7.3L DIESEL - WHEN COMING TO A STOP OR WHEN CLUTCH IS DISENGAGED
LIGHT TRUCK:
1983-94 ECONOLINE, F SUPER DUTY, F-250, F-350
ISSUE:
The engine may stall when coming to a stop or after clutch disengagement. This may be caused by one or more of the following:
^ System-related conditions identified using the Diesel Engine Performance Chart.
^ Fuel injection pump contamination or
^ Use of low lubricity fuel.
ACTION:
Use the Diesel Engine Performance Chart and the following procedure to diagnose and repair the stall condition.
DETAILED SERVICE PROCEDURE
Completing the Engine Performance Chart assists technicians in identifying and resolving diesel engine stalling concerns caused by system-related conditions, such as fuel system restrictions.
Complete the "Engine Performance Chart - Diesel Engine Diagnostic Guide"
^ 7.3L base engine - FPS-8512-C;
^ 7.3L turbo-charged engine - FPS20269101;
^ 6.9L engine - FPS-8433-C giving additional attention to the following items:
a. "Fuel Quality Check"
b. "Fuel Supply System Check"
c. "Fuel Return Line Pressure Check"
d. "Low Idle (RPM) Check" - (make sure that idle RPM is not set below RPM designated on Emissions Label)
e. "Injection Pump Timing Check"
NOTE:
DO NOT REPLACE THE FUEL INJECTION PUMP UNLESS:
^ INJECTION PUMP TIMING ADVANCE IS NOT AT SPECIFICATION (REFER TO ENGINE PERFORMANCE CHART), OR
^ INJECTION PUMP TRANSFER PRESSURE (MEASURED AT THE RPM DESIGNATED ON THE ENGINE PERFORMANCE CHART) IS NOT AT SPECIFICATION.
Perform vehicle road test to verify effectiveness of any corrections made during the diagnostic procedure.
IF ENGINE STALL CONCERN HAS BEEN RESOLVED, DO NOT PROCEED ANY FURTHER.
2. Remove the governor assembly cover from the injection pump using the "Governor Cover Assembly And Gasket Removal And Installation Procedure Below. Visually inspect the inside of the pump:
a. If a red rust color is present, excessive water has run through the pump. Replace the injection pump, drain the water separator, replace the fuel filter and clean and test the "Water In Fuel" sensor for proper operation.
b. If a black sludge is present, the fuel system is contaminated. Flush the fuel system completely, replace the injection pump, drain the water separator, replace the fuel filter, and clean and test the "Water In Fuel" sensor for proper operation.
c. If the pump is clean inside, the pump is fully functional. Reinstall the Governor Cover assembly to the injection pump using the Governor Cover Assembly And Gasket Removal And Installation Procedure which follows.
COVER ASSEMBLY AND GASKET REMOVAL AND INSTALLATION PROCEDURES
REMOVAL
CAUTION:
CLEAN THE TOP OF THE THE PUMP WITH SOLVENT BEFORE REMOVING THE GOVERNOR COVER ASSEMBLY. EXTREME CARE MUST BE TAKEN TO PREVENT DIRT OR FOREIGN MATERIAL FROM ENTERING THE INJECTION PUMP TO PREVENT PUMP DAMAGE.
1. Disconnect the battery.
2. Disconnect the Fuel Shut-Off (F.S.O.) and Housing Pressure Cold Advance (H.P.C.A.) solenoid wires from the governor and remove the fuel return line connector fitting and seal from the top of the governor cover, Figure 1.
3. Remove the seal wire (if applicable).
4. Remove the three (3) governor cover screws and washers, Figure 2.
5. Remove the governor cover and gasket.
INSTALLATION
1. Carefully install the governor cover assembly to the pump as follows, Figure 3:
a. Make sure the screws are NOT in the governor cover.
b. Position the governor cover about 1/4" forward of its final alignment (toward the front of the vehicle and about 1/8" above the pump).
c. Move the cover rearward and downward into position so that the arm contacts the link, being careful not to roll the gasket, Figure 3.
d. With the cover on the pump and before installing the screws, move the governor cover forward and backward until preload of the internal spring is felt, indicating that the F.S.O. is NOT binding internally.
e. Reinstall the three (3) governor cover screws with one flat washer and one lock washer with each screw. The flat washer must be against the pump cover. Screw with the seal wire hole must be in the rear position of the governor cover. Tighten screws to 4.5 N-m (40 lb.in.), Figure 2.
NOTE:
THE LOCK WASHER FOR THE GOVERNOR COVER ASSEMBLY MUST BE INSTALLED BETWEEN THE TERMINAL GROUNDING STRAP AND THE GOVERNOR COVER BEFORE INSTALLING THE SCREW IN THAT CORNER. REFER TO FIGURE 4.
f. Turn the ignition switch to the "RUN" position, and touch the red F.S.O. solenoid wire to the solenoid terminal. A clicking noise should be heard as the wire is connected and disconnected.
CAUTION:
THE IGNITION SWITCH SHOULD NOT BE LEFT IN THE "RUN" POSITION WITH THE F.S.O. SOLENOID CONNECTED FOR EXTENDED PERIODS OF TIME. DAMAGE TO THE F.S.O. SOLENOID MAY OCCUR.
WARNING:
IF F.S.O. CLICKING IS NOT HEARD/OBSERVED, THE FUEL METERING LINKAGE MAY BE JAMMED IN THE WIDE OPEN POSITION. THE ENGINE MUST NOT BE STARTED IF CLICKING IS NOT HEARD, AS A RUNAWAY ENGINE CONDITION MAY OCCUR, RESULTING IN SERIOUS ENGINE DAMAGE AND POSSIBLE BODILY HARM. THE ENGINE CANNOT BE SHUT OFF IF IT IS STARTED WITH JAMMED FUEL METERING LINKAGE.
2. If F.S.O. clicking is NOT heard/observed:
a. DO NOT start the engine.
b. Check for battery voltage (minimum 10 volts) at F.S.O. connector, Figure 5:
^ If no voltage, service open circuit in wiring and repeat solenoid "click" check.
^ If voltage is present, continue to next step.
c. Remove the governor cover. Check engagement of F.S.O. and internal governor components. Refer to Figure 3.
d. Reinstall the cover carefully, following the previous instructions in step 1, and observe that F.S.O. clicking is heard.
3. If F.S.O. clicking is heard/observed:
a. Turn off ignition switch.
b. Connect the F.S.O. and H.P.C.A wires.
c. Reinstall original return line connector fitting with a new connector fitting seal (if appropriate).
d. Reinstall the fuel return line.
e. Start engine and check for leaks.
f. If no leaks are evident, install new seal wires (if appropriate) and crimp the seal, Figure 2.
Perform vehicle road test to verify effectiveness of any service procedures performed.
IF ENGINE STALL CONCERN HAS BEEN RESOLVED, DO NOT PROCEED ANY FURTHER.
4. Try different blends / suppliers of # 2D diesel fuel (winter blend # 2D fuel for temperatures below 20~ F) or add "Stanadyne All Season Diesel Fuel Conditioner" to fuel per directions on the container. Conditioner may require using one full tank of fuel to take full effect, but often begins working after driving 2-5 miles. Other brands of conditioners or additives are not recommended. The Stanadyne conditioner was tested and found to be the best available product for resolving the low lubricity fuel-related engine stalling concern without adverse side effects. Case lots of the conditioner can be purchased through Stanadyne Regional Distributors, Figure 6. Individual bottles of the conditioner can be purchased through many Stanadyne and John Deere dealers:
5. Refer to Figure 6 for a list of Stanadyne Regional Distributors.
Please contact the distributor nearest you.
OTHER APPLICABLE ARTICLES: NONE
WARRANTY STATUS:
Eligible Under Bumper To Bumper Warranty Coverage For 1992-94 Model Years. Eligible Under Basic Warranty Coverage And Powertrain For 1983-91 Model Years. Eligible Under Emission Coverage For All Model Years.
OPERATION DESCRIPTION TIME
940511A Remove Governor Cover, 0.7 Hr.
Check For Presence Of
Rust Or Sludge, Re-install
Cover - F-Series
940511B Remove Governor Cover, 0.8 Hr.
Check For Presence Of
Rust Or Sludge, Re-install
Cover - E-Series
940511C Additional Time To Replace 2.6 Hrs.
Fuel Injection Pump, Clean,
Test (and replace if
necessary) The "Water In
Fuel" Sensor, Replace Fuel
Filter - F-Series
940511D Additional Time To Replace 3.1 Hrs.
Fuel Injection Pump, Clean,
Test (and replace if
necessary) The "Water In
Fuel" Sensor, Replace Fuel
Filter - E-Series
940511E Additional Time To Flush 0.5 Hr.
Fuel Lines - All Vehicles
DEALER CODING
BASIC PART NO. CONDITION CODE
9A543 49
OASIS CODES: 607000