3412 Generator Set Caterpillar

Engine Top Speed Is Not Obtained

Usage:

3412 DK6

Probable Causes

Cold mode
Engine derate or active codes
Programmable parameters
Throttle position signal
Fuel supply
Air inlet and exhaust system
Inlet manifold pressure
Rack controls
Electrical connectors

Note: If the problem only occurs under certain conditions, test the engine under those conditions. Examples of certain conditions are high engine speed, full load, and engine operating temperature. Troubleshooting the symptoms under other conditions can give misleading results.

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Table 1
Troubleshooting Test Steps	Value	Results
1. Check the Engine for Cold Mode Operation.	Cold Mode	Result : The engine is NOT in cold mode. Proceed to Test Step 2. Result : The engine is in cold mode. Repair : Cold mode is activated whenever the engine coolant temperature falls below a predetermined value. Cold mode remains active until the engine has warmed, or a time limit is exceeded. If the problem is not resolved, proceed to Test Step 2.
2. Check for Engine Derate or Active Diagnostic Codes. A. Some engine monitoring parameters can trigger an engine derate do not produce an event code. Connect Cat^® Electronic Technician (ET) in order to check for a derate of the engine. Certain diagnostic codes may cause poor performance. Use Cat ET to check for active codes and for logged codes. Note : Although a sensor signal may be in the operational range of the sensor, the signal may not represent the actual reading. Use Cat ET to check that the pressures and the temperatures are fluctuating. Also, check that the values are reasonable for the conditions that are present.	Engine derate Active diagnostic codes	Result : The engine derate and/or active diagnostic codes are not present. Proceed to Test Step 3. Result : The engine derate and/or diagnostic codes are present. Repair : Troubleshoot any codes that are present before you continue with this procedure. If the problem is not resolved, proceed to Test Step 3.
3. Record the Full Load Settings and the Full Torque Settings. A. The settings should be programmed to the values on the engine information plate.	Programmable parameters	Result : The programmable parameters are OK. Proceed to Test Step 4. Result : The programmable parameters are NOT OK. Repair : Refer to Troubleshooting, "Programmable Parameters" for more information. If the problem is not resolved, proceed to Test Step 4.
4. Monitor the Status for "Throttle Position" on Cat ET. A. Verify that the status for "Throttle Position" is stable and that the engine is able to reach high idle speed.	"Throttle Position"	Result : The "Throttle Position" is OK. Proceed to Test Step 5. Result : The "Throttle Position" is NOT OK. Repair : If a problem is suspected with the throttle, refer to the appropriate troubleshooting procedure for troubleshooting the throttle signal. If the problem is not resolved, proceed to Test Step 5.
5. Visually Check the Fuel Level in the Fuel Tank. A. Do not rely on the fuel gauge only.	Fuel level	Result : The fuel level is OK. Proceed to Test Step 6. Result : The fuel level is NOT OK. Repair : Add fuel to the fuel tank. If the engine has been run out of fuel, it will be necessary to purge the air from the fuel system. Refer to Operation and Maintenance Manual for the correct procedure. If the problem is not resolved, proceed to Test Step 6.
6. Check the Fuel Lines. A. Check for restrictions, collapsed lines, and pinched lines.	Fuel lines	Result : The fuel lines are OK. Proceed to Test Step 7. Result : The fuel lines are NOT OK. Repair : If problems are found with the fuel lines, repair the lines and/or replace the lines. If the problem is not resolved, proceed to Test Step 7.
7. Check the Fuel Tank for Debris or Foreign Objects Which May Block the Fuel Supply.	Fuel tank	Result : The fuel tank is OK. Proceed to Test Step 8. Result : The fuel tank is NOT OK. Repair : Clean the fuel tank of any foreign debris. 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 If the problem is not resolved, proceed to Test Step 8.
8. Check fuel quality. Note : Cold weather adversely affects the characteristics of the fuel.	Fuel quantity	Result : The fuel quantity is OK. Proceed to Test Step 6. Result : The fuel quantity is NOT OK. Repair : Refer to the engine Operation and Maintenance Manual for information on improving the characteristics of the fuel during cold-weather operation. If the problem is not resolved, proceed to Test Step 9.
9. Check that the Filtered Fuel Pressure While the Engine is being Cranked. A. Refer to Systems Operation/Testing and Adjusting for the test procedure and for the correct pressure values.	Fuel pressure	Result : The fuel pressure is OK. Proceed to Test Step 10. Result : The fuel pressure is NOT OK. Repair : If the fuel pressure is low, replace the fuel filters. Clean the primary filter/water separator of debris. Refer to the Operation and Maintenance Manual for details. If the fuel pressure is still low, check the operation of the fuel pressure regulating valve. Also, check for the proper operation of the fuel transfer pump. Refer to Systems Operation/Testing and Adjusting for test information. If the problem is not resolved, proceed to Test Step 10.
10. Check for an Air Filter Restriction.	Air filter restriction	Result : The air filter restriction is OK. Proceed to Test Step 11. Result : The air filter restriction is NOT OK. Repair : Clean plugged air filters or replace plugged air filters. Refer to the Operation and Maintenance Manual. If the problem is not resolved, proceed to Test Step 11.
11. Check the Air Inlet and Exhaust System for Restrictions and/or Leaks.	Air inlet and/or Exhaust restrictions or leaks	Result : The air inlet and/or exhaust systems are OK. Proceed to Test Step 12. Result : The air inlet and/or exhaust systems are NOT OK. Repair : Refer to Systems Operation/Testing and Adjusting for information on inspecting the air inlet and exhaust system. If the problem is not resolved, proceed to Test Step 12.
12. Check the Inlet Manifold Pressure Sensor for Proper Operation. A. The calibration should also be checked.	Intake manifold pressure sensor	Result : The intake manifold pressure sensor is OK. Proceed to Test Step 13. Result : The intake manifold pressure sensor is NOT OK. Repair : Refer to Troubleshooting, "Inlet Manifold Pressure - Test" for troubleshooting procedures. If the problem is not resolved, proceed to Test Step 13.
13. Check the Rack Solenoid for Proper Operation.	Rack solenoid	Result : The rack solenoid is OK. Proceed to Test Step 14. Result : The rack solenoid is NOT OK. Repair : Refer to Troubleshooting, "Fuel Rack Solenoid - Test" for troubleshooting procedures. Refer to Troubleshooting, "Fuel Control - Test" in order to troubleshoot the Dynamic Rack Controls. Refer to Troubleshooting, "Sensor Signal (Analog, Active) - Test" for procedures to troubleshoot the rack position sensor. If the problem is not resolved, proceed to Test Step 14.
14. Check for Correct Installation of the J1/P1 ECM Connector.	ECM connector	Result : The J1/P1 ECM connector is NOT OK. Repair : Refer to Troubleshooting, "Electrical Connectors - Inspect".