44104A 2 Mercury FORWARD GEAR ASSEMBLY

Recommended Actions
Table 1
Troubleshooting Test Steps Values Results
1. Certain diagnostic codes and/or event codes may prevent the engine from starting
A. Connect the Cat® Electronic Technician (ET) and check for active codes and/or for logged codes.
Diagnostic Codes
Results: Active codes were found when connected to Cat ET.
Repair: Troubleshoot any codes that present before continuing with this procedure.
Result: No active codes were found when connected to Cat ET.
Proceed to Test Step 2.
Note: If Cat ET will not communicate with the ECM, the problem is most likely with the electrical power supply to the ECM. Refer to the diagnostic functional test Troubleshooting, "Electrical power Supply Circuit - Test".
2. Test the operation of the starting motor and associated circuit components
Starting Circuit
Result: Faults were found when testing the starting motor and associated circuit components.
Repair: Refer to the Systems Operation and the Testing and Adjusting manual.
Result: No faults were found when testing the starting motor and associated circuit components.
Proceed to Test Step 3.
3. Ensure that correct flash file is properly installed on the ECM
Note: A new ECM is not programmed to any specific engine until a flash file has been installed. The engine will not start and will not communicate with Cat ET until the flash file has been downloaded.
Flash File
Result: Flash file is not installed properly on the ECM.
Repair: Download the correct flash file and install properly to the ECM.
Result: The correct flash file is properly installed on the ECM.
Proceed to Test Step 4.
4. Starting Aids (If Applicable)
A. Inspect that the air inlet heater is programmed to the On position.
B. Inspect that the ether injection system is programmed to "On".
Starting Aids are Operational
Result: The starting aid is operating correctly.
Proceed to Test Step 5.
Result: The air inlet heater is programmed to the Off position.
Repair: Reprogram the air inlet heater to the On position.
Refer to the diagnostic functional test Troubleshooting, "Air Inlet Heater Circuit - Test"
Result: The ether injection system is programmed to "Off".
Repair: Reprogram the ether injection system to "On".
Refer to the diagnostic functional test Troubleshooting, "Ether Injection System - Test".
5. Engine Shutdown Switches (If Applicable)
A. The engine shutdown switches must be in the OFF position.
Note: If Cat ET will not communicate with the ECM, the problem is most likely with the electrical power supply to the ECM. Refer to the diagnostic functional test Troubleshooting, "Electrical Power Supply Circuit - Test".
Switches are in the OFF position
Result: The switches are in the OFF position.
Proceed to Test Step 6.
Result: The switches are not in the OFF position.
Repair: Turn the switches to the OFF position. STOP. Verify that the repair eliminated the problem.
6. Crank Without Inject (If Applicable)
A. Ensure the crank without inject circuit is not active.
Inject Circuit
Result: The crank without inject circuit is not active.
Proceed to Test Step 7.
Result: The crank without inject circuit is active.
Repair: Proceed to Troubleshooting , "Crank Without Inject Circuit - Test".
7. Air Shutoff System (If Applicable)
A. Check the operation of the air shutoff system.
Air Shutoff
Result: The air shutoff system is operating properly.
Proceed to Test Step 8.
Result: The air shutoff system is not operating properly. Refer to Troubleshooting, "Air Shutoff - Test" for troubleshooting information. Verify that the repair eliminated the problem.
8. Engine Speed/Timing
A. Crank the engine and observe that the engine speed on the Cat ET status screen is not zero rpm.
Note: Upon initial cranking, the status for engine speed may indicate that the engine speed signal is abnormal. This message will be replaced with an engine speed once the ECM is able to calculate a speed from the signal.
B. Inspect that the timing reference gear is installed correctly and not installed backwards, preventing the engine from starting.
C. Check for proper orientation between the crankshaft and camshaft drive gears.
Notice: Do not crank the engine continuously for more than 30 seconds. Allow the starting motor to cool for 2 minutes before cranking the engine again.
Speed/Timing
Result: Cat ET status screen indicates the correct engine rpm.
Proceed to Test Step 9.
Result: Cat ET status screen shows zero engine rpm.
Repair: Refer to the diagnostic functional test Troubleshooting, "Engine Speed/Timing Sensor Circuit - Test".
Result: The gear was properly oriented and installed correctly on the engine.
Proceed to Test Step 9.
Result: The timing reference gear was not properly oriented and not installed correctly.
Repair: Correct the orientation and/or replace the drive gear, if necessary.
Refer to the Disassembly and Assembly manual.
9. Fuel Supply Pressure
A. Visually check the fuel level. Do not rely on the fuel gauge only. If necessary, add fuel. If the engine has been run out of fuel, purge the air from the fuel system.
B. Check the fuel lines for the following problems:
- Restrictions
- Collapsed Lines
- Pinched Lines
- Loose Connections
C. Check the fuel tank for foreign objects which may block the fuel supply.
D. Prime the fuel system if any of the following procedures have been performed:
- Replacement of the fuel filters
- Service on the low-pressure fuel supply circuit
- Replacement of unit injectors
E. Check the fuel quality.
Cold weather adversely affects the characteristics of the fuel. Refer to the Operation and Maintenance Manual for information on improving the characteristics of the fuel during cold-weather operation.
F. Check the fuel pressure after the fuel filter while the engine is being cranked. Ensure that the fuel is stable. Refer to the Systems Operation/Testing and Adjusting for the procedure to check the fuel pressure manually.
Note: Do not crank the engine continuously for more than 30 seconds. Allow the starting motor to cool for 2 minutes before cranking the engine again.
Low-Pressure Fuel System
Result: The low-pressure fuel system is operating properly.
Proceed to Test Step 10.
Result: The fuel supply is not operating properly.
Repair: If the fuel pressure is low, replace the fuel filters. If the fuel pressure is still low, check the following items:
-Fuel Transfer Pump
-Fuel Transfer Pump Coupling
Fuel Pressure Regulating Valve
Verify that the repair eliminated the problem.
10. Electronic Unit Injectors
A. Perform the "Injector Solenoid Test" on Cat ET in order to determine if all of the injector solenoids are being energized by the ECM.
B. Perform the "Cylinder Cutout Test" in order to identify any injectors that might be misfiring.
Note: Refer to the procedure in Special Instruction, "Procedure for Troubleshooting