821354 2 Mercury FACE PLATE

Recommended Actions
Do not crank the engine continuously for more than 30 seconds. Allow the starting motor to cool for two minutes before cranking the engine again.
Note: The procedures have been listed in order of probability. Complete the procedures in order.
Table 1
Troubleshooting Test Steps Values Results
1. Diagnostic Codes
A. Turn the keyswitch to the ON position.
B. Connect the electronic service tool to the diagnostic connector.
C. Use the electronic service tool to check for active or logged codes.
Diagnostic Codes
Result: A diagnostic code is present.
Troubleshoot the diagnostic code. Refer to Troubleshooting, "Diagnostic Trouble Codes".
Result: A diagnostic code is not present.
Proceed to Test Step 2.
2. Visible Faults
A. Visually inspect the engine for the following faults:
Missing components
Damaged components
Damaged electrical cables or loose electrical cables
Oil leaks
Fuel leaks
B. Check for the correct level of fuel, oil, and coolant.
C. Ensure that the fuel supply valve (if equipped) is in the OPEN position.
D. If the ambient temperature is below 0 °C (32 °F), make sure that the correct specification of engine oil and oil for the machine is used.
E. Check that the battery voltage is correct.
F. Use the electronic service tool to check the average cranking speed of the engine. If the cranking speed is less than 150 rpm, investigate the cause of the low cranking speed.
G. Make sure that all fuel filters are correctly installed.
H. Drain any water from the primary fuel filter/water separator, if equipped.
Visible faults
Result: Faults identified during the inspection.
Make any necessary repairs.
Result: No faults identified.
Proceed to Test Step 3.
3. Air Intake and Exhaust System
A. Check the air filter restriction indicator, if equipped. Replace a plugged air filters. Refer to the Operation and Maintenance Manual.
B. Check the air inlet and exhaust system for restrictions and/or leaks.
Restrictions
Result: There are restrictions in the air inlet or exhaust system.
Make the necessary repairs, Refer to Systems Operation/Testing and Adjusting, "Air Inlet and Exhaust System - Inspect" for additional information.
Result: There are no restrictions in the air inlet or exhaust system.
Proceed to Test Step 4.
4. Speed Sensors
A. Disconnect the connector from the primary speed sensor.
B. Attempt to start the engine.
C. If the engine starts, check for a fault in the circuit for the primary speed sensor. Refer to Troubleshooting, "Speed/Timing - Test".
D. If the engine does not start, inspect the drive gear on the crankshaft for damage.
E. If necessary, repair the drive gear or replace the crankshaft. Refer to Disassembly and Assembly, "Crankshaft - Remove" and Disassembly and Assembly, "Crankshaft - Install".
F. Connect the electronic service tool to the diagnostic connector.
G. Use the electronic service tool to check the signal from the secondary speed sensor while the engine is cranking.
H. If the signal from the secondary speed sensor is 0 rpm, investigate the secondary speed sensor. Refer to Troubleshooting, "Speed/Timing - Test".
Speed sensor faults
Result: Speed sensor faults identified.
Make any necessary repairs.
If the engine will still not start, proceed to Test Step 5.
Result:The speed sensors are OK.
Proceed to Test Step 5.
5. Fuel System
A. Visually check the fuel level in the fuel tank. Do not rely on the fuel gauge only.
B. Ensure that the vent in the fuel cap is not filled with debris.
C. Ensure that the fuel supply valve (if equipped) is in the full OPEN position.
D. If the temperature is below 0 °C (32 °F), check for solidified fuel (wax).
E. Check the primary filter/water separator for water in the fuel.
F. Check for fuel supply lines that are restricted.
G. Check that the low-pressure fuel lines are tight and secured properly.
H. Check that the Electric Fuel Lift Pump (EFLP) is operating. If the EFLP is suspect, refer to Troubleshooting, "Relay - Test (Electric Fuel Lift Pump)".
I. Replace the primary and secondary fuel filters.
J. Check the diesel fuel for contamination. Refer to Systems Operation, Testing, and Adjusting, "Fuel Quality - Test".
K. Check for air in the fuel system. Refer to Systems Operation, Testing, and Adjusting, "Air in Fuel - Test".
L. Ensure that the fuel system has been primed. Refer to Systems Operation, Testing, and Adjusting, "Fuel System - Prime".
M. Check the operation of the fuel injectors. Refer to Systems Operation, Testing, and Adjusting, "Fuel Injector - Test".
Fuel system
Result: The fuel supply is not OK.
Repair the fuel system or replace the fuel system components, as necessary.
Result: The fuel supply is OK.
Proceed to Test Step 6.
6. Glow Plugs
A. Check the operation of the glow plugs. Refer to Systems Operation, Testing and Adjusting, "Glow Plugs - Test".
Glow Plugs
Result: One or more of the glow plugs are faulty.
Replace any faulty glow plugs. Refer to Disassembly and Assembly, "Glow Plug - Remove and Install".
Result: The glow plugs are OK.
Proceed to Test Step 7.
7. Low Compression (Cylinder Pressure)
A. Perform a compression test. Refer to Systems Operation, Testing, and Adjusting, "Compression - Test ".
Cylinder compression
Result: The results of the compression test are outside the specifications.
Investigate the cause and rectify any faults.
Note: Possible causes of low compression are shown in the following list:
Loose glow plugs
Faulty piston
Faulty piston rings
Worn cylinder bores
Worn valves
Faulty cylinder head gasket
Damaged cylinder head
Result: The results of the compression test are OK.
Contact the Technical Communicator at a Cat Dealer.