3126B Petroleum Engine Caterpillar

Use the steps that follow to check the operation of the HEUI fuel system. Circle the appropriate answer in the "Results" section of each test step. Complete all of the test steps that are in this procedure. Return the pages of this procedure with any of the requested parts through Caterpillar's return system.

Illustration 1	g01130179
Component locations (typical example) (1) Unit injector hydraulic pump (2) Injection actuation pressure sensor (3) Injection Actuation Pressure Control Valve (IAPCV) (4) High pressure supply line to cylinder head (5) Low pressure supply line to pump (6) Electronic Control Module (ECM) (7) J2/P2 ECM connector

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The connection of any electrical equipment and the disconnection of any electrical equipment may cause an explosion hazard which may result in injury or death. Do not connect any electrical equipment or disconnect any electrical equipment in an explosive atmosphere.

Test Step 1. Symptoms

The following symptoms may occur if there is a problem with the HEUI fuel system:

• The engine cranks but the engine will not start.

• The engine runs rough.

• The engine is erratic or unstable at idle or running.

• Low power

The following diagnostic codes might be currently active or logged:

• 164-00 High Injectuation Actuation Pressure

• 164-02 Injectuation Actuation Pressure signal irratic

• 164-11 Injectuation Actuation Pressure system fault

1. Connect the Caterpillar Electronic Technician (ET) to the service tool connector.

2. Turn the keyswitch to the ON position. DO NOT START THE ENGINE.

3. Print the "Lifetime Totals" and the "Configuration" screen.

4. Check for active diagnostic codes.

Expected Result:

There are no active diagnostic codes with the keyswitch in the ON position while the engine is off.

Results:

• OK - None of these codes are active with the keyswitch in the ON position while the engine is off. Proceed to Test Step 2.

• Not OK - 164-03 or 164-04 is active with the keyswitch in the ON position while the engine is off.

  Repair: Refer to Troubleshooting, "Engine Pressure Sensor Open or Short Circuit - Test".

  STOP

• Not OK - A 164-02 diagnostic code is active with the keyswitch in the ON position while the engine is off.

  Repair: Refer to Troubleshooting, "Injection Actuation Pressure Sensor - Test".

  STOP

• Not OK - 164-00 or 164-11 is active with the keyswitch in the ON position while the engine is off.

  Repair: Contact your Engine Technical Communicator (TC).

  STOP

Test Step 2. Check the Engine Oil Level

1. Check the engine oil level. Refer to Operation and Maintenance Manual, "Engine Oil Level - Check".

2. If the engine oil level is low add oil to the engine.

3. Try to start the engine.

Expected Result:

The engine has started.

Results:

• OK - The engine starts. Proceed to Test Step 9.

• Not OK - The engine does not start. Proceed to Test Step 3.

Test Step 3. Crank the Engine and Record the Engine Data From Cat ET

Your answer indicated that the engine oil level is satisfactory.

1. Crank the engine and observe the "Injection Actuation Pressure" and "Engine RPM".

   ________ Record the actual injection actuation pressure.

   ________ Record the engine speed.

Expected Result:

The injection actuation pressure is above 6 MPa (870 psi).

Results:

• OK - The injection actuation pressure is above 6 MPa (870 psi).

  Repair: The HEUI system is functioning correctly. Refer to Troubleshooting, "Engine Cranks but Will Not Start" which is located in the "Troubleshooting without a Diagnostic Code" section.

  STOP

• Not OK - The injection actuation pressure is below 6 MPa (870 psi). Proceed to Test Step 4.

Test Step 4. Check the Oil Pressure at the Fuel Injection Pump Outlet Port

Disconnect the high pressure oil line from the cylinder head and install the 8T-0852 Pressure Gauge to the fuel injection pump outlet port. Crank the engine and record the oil pressure.

Note: The pressure readings may vary between gauges.

________ Observed pressure reading

________ Observed RPM

________ Observed "Injection Actuation Output Percent"

Expected Result:

The oil pressure is above 27.5 MPa (4000 psi).

Results:

• OK - The oil pressure is above 27.5 MPa (4000 psi).

  Repair: Remove the pressure gauge from the engine.

  Proceed to Test Step 8.

• Not OK - The oil pressure is below 27.5 MPa (4000 psi). Proceed to Test Step 5.

Test Step 5. Install a Test Plug and Recheck the Oil Pressure

1. Remove the Injection Actuation Pressure Control Valve (IAPCV).

2. Install a 219-2368 Plug and 9X-1484 Seal Kit and perform the pressure test at the fuel injection pump outlet port. Crank the engine and record the results.

   ________ Observed pressure reading

   Note: If the 219-2368 Plug is not available, proceed to "Install a New IAPCV and Check the Oil Pressure".

Expected Result:

The oil pressure is above 27.5 MPa (4000 psi).

Results:

• OK - The oil pressure is above 27.5 MPa (4000 psi). The HEUI pump is OK.

  Repair: Replace the IAPCV and recheck the oil pressure. If the problem continues contact technical support.

  STOP

• Not OK - The oil pressure is below 27.5 MPa (4000 psi).

  Repair: Remove the pressure gauge from the engine.

  Proceed to Test Step 7.

Test Step 6. Install a New IAPCV and Check the Oil Pressure

Note: Use this Test Step only if the 219-2368 Plug is not available.

1. Install a new IAPCV onto the high pressure oil pump. Refer to Disassembly and Assembly, "Injection Actuation Pressure Control Valve - Remove and Install".

2. Check the oil pressure at the fuel injection pump outlet port. Record the pressure reading.

   ________ Observed pressure reading

Expected Result:

The oil pressure measures above 27.5 MPa (4000 psi).

Results:

• OK - The oil pressure is above 27.5 MPa (4000 psi).

  Repair: The replacement of the IAPCV has corrected the problem. Remove the test equipment from the engine. Verify that the repair has resolved the problem.

  STOP

• Not OK - The oil pressure is below 27.5 MPa (4000 psi).

  Repair: Remove the new IAPCV and reinstall the original IAPCV.

  Proceed to Test Step 7.

Test Step 7. Check the Fuel Injection Pump Drive Gear

1. Remove the high pressure oil pump. Refer to Disassembly and Assembly, "Unit Injector Hydraulic Pump - Remove".

2. Check for any physical damage to the drive gear.

3. Verify that the drive gear and the retaining bolt are properly tightened. Also verify that the pump shaft rotates freely.

Expected Result:

The drive gear and the retaining bolt for the high pressure oil pump are tight. The pump shaft rotates freely.

Results:

• OK - The drive gear bolt is properly tightened and the pump shaft rotates freely.

  Repair: Replace the high pressure oil pump. Refer to Disassembly and Assembly, "Unit Injector Hydraulic Pump - Install". Verify that the repair has resolved the problem. If this does not fix the problem, contact technical support.

  STOP

• Not OK - The pump shaft does not rotate freely.STOP

• Not OK - The drive gear bolt is loose. The pump shaft rotates freely and there is no obvious mechanical damage that would indicate a different problem.

  Repair: Replace the drive gear, if necessary. Tighten the drive gear bolt. Refer to Specifications, "Unit Injector Hydraulic Pump". Reinstall the pump. Refer to Disassembly and Assembly, "Unit Injector Hydraulic Pump - Install". Recheck the pressure in order to ensure that the problem has been resolved.If this does not fix the problem, replace the high pressure oil pump. Verify that the repair has resolved the problem.

  STOP

Test Step 8. Check the High Pressure Oil System for Leaks

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Hot oil and components can cause personal injury. Do not allow hot oil or components to contact skin.

1. Remove the valve cover and inspect the high pressure oil system for oil leaks.

2. While the engine is being cranked, inspect the area around the injector bores for any signs of oil leakage. Inspect the spill ports of the injector for excessive oil. All six injectors should spill the same amount of oil.

Expected Result:

No leaks are apparent.

Results:

• OK - The high pressure oil system is not leaking.

  Repair: Call technical support for assistance.

  STOP

• Not OK - A leak in the high pressure oil system has been found.

  Repair: Replace the O-ring on the injector or replace the damaged injector. Verify that the repair has resolved the problem.

  STOP

Test Step 9. Operate the Engine and Check for Diagnostic Codes

1. Turn the keyswitch to the ON position. Start the engine.

2. While the engine is running, use Cat ET to check for the following diagnostic codes:

• 164-00

• 164-02

• 164-11

Place a check beside the codes that are active or logged.

• ________ 164-00

• ________ 164-02

• ________ 164-11

Stop the engine.

Expected Result:

None of the diagnostic codes are active.

Results:

• OK - None of the diagnostic codes that are mentioned above are active. Proceed to Test Step 10.

• Not OK - Either a 164-00 or a 164-11 is active. A 164-02 may also be active at this time. Proceed to Test Step 10.

• Not OK - 164-02 is active, but 164-00 and 164-11 are not active at this time.

  Repair: Refer to Troubleshooting, "Injection Actuation Pressure Sensor - Test".

  STOP

Test Step 10. Evaluate the Quality of the Oil

Extended oil drain intervals may affect the operation of the HEUI high pressure oil system. Refer to the Operation and Maintenance Manual, "Engine Oil" for additional information concerning proper oil change intervals.

1. Check the maintenance records for the engine. Ensure that the customer has not exceeded the suggested oil change interval.

Expected Result:

The customer has not exceeded the suggested oil change interval and an oil change does not need to be performed.

Results:

• OK - The engine has been properly maintained. Proceed to Test Step 11.

• Not OK - The customer has exceeded the suggested oil change interval for the engine.

  Repair: Perform an oil change on the engine. Refer to Operation and Maintenance Manual, "Engine Oil and Filter - Change".Run the engine throughout the operating rpm range for 10 to 15 minutes. This will purge any trapped air or debris that is in the system.

  If the problem still exists or if the problem recurs in a short period or time, proceed to Test Step 11.

Test Step 11. Perform the "Injection Actuation Pressure Test"

1. Install 8T-0852 Pressure Gauge on the high pressure oil rail.

2. Connect Cat ET to the service tool connector.

3. Perform the "Injection Actuation Pressure Test" in the using Cat ET. Record the results in Table 1.

   Note: The "Injection Actuation Pressure Test" can be used to vary the injection actuation pressure. The test adjusts the oil pressure in steps. Some versions of Cat ET may have three steps in the test and some versions of Cat ET may have four steps in the test.

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   Table 1

   Step	Manual Pressure gauge	Cat ET	Difference
   1
   2
   3
   4

Expected Result:

The pressure that is measured with the pressure gauge for each step and the pressure that is displayed on Cat ET for each step are within 1379 kPa (200 psi).

Results:

• OK - The pressure difference is within specifications. The injection actuation pressure sensor is operating properly. Proceed to Test Step 12.

• Not OK - The pressure difference is not within specifications.

  Repair: The injection actuation pressure sensor may be faulty. Replace the sensor and repeat this test step.

  If the problem still exists, reinstall the original sensor and proceed to Test Step 12.

Test Step 12. Perform the "Injection Actuation Pressure Test" at both Low Idle and at High Idle

Start the engine. Perform the "Injection Actuation Pressure Test" at low idle and at high idle.

Record the results in Table 2.

Expected Result:

The "Injection Actuation Pressure Output" never exceeds 65 percent and "Injection Actuation Pressure Output" is never reduced to zero percent.

Results:

• OK - The "Injection Actuation Pressure Output" is within specifications.

  Repair: Call technical support for assistance.

  STOP

• Not OK - The "Injection Actuation Pressure Output" is not within specifications. Proceed to Test Step 13.

Test Step 13. Install a New IAPCV and Retest the System

Install a new IAPCV and perform the "Injection Actuation Pressure Test" at low idle and at high idle.

Record the results in Table 3.

Expected Result:

The "Injection Actuation Pressure Output" never exceeds 65 percent and "Injection Actuation Pressure Output" is never reduced to zero percent.

Results:

• OK - The "Injection Actuation Pressure Output" is within specifications.

  Repair: Verify that the repair has resolved the problem.

  STOP

• Not OK - The "Injection Actuation Pressure Output" is not within specifications. Reinstall the original IAPCV. Proceed to Test Step 14.

Test Step 14. Check the Oil Pressure

1. Remove the IAPCV. Refer to Disassembly and Assembly, "Injection Actuation Pressure Control Valve - Remove and Install".

2. Replace the IAPCV with a 219-2368 Plug and 9X-1484 Seal Kit .

3. Disconnect the high pressure oil line from the cylinder head and install the 8T-0852 Pressure Gauge onto the line. Crank the engine and record the oil pressure.

Note: The pressure readings may vary between gauges.

________ Observed pressure reading

________ Observed RPM

Expected Result:

The oil pressure is above 27.5 MPa (4000 psi).

Results:

• OK - The oil pressure is above 27.5 MPa (4000 psi). The high pressure oil pump is operating correctly. Proceed to Test Step 16.

• Not OK - The oil pressure is below 27.5 MPa (4000 psi).

  Repair: The high pressure oil pump may be faulty. Remove the pressure gauge from the engine.

  Proceed to Test Step 15.

Test Step 15. Check the Fuel Injection Pump Drive Gear

1. Remove the high pressure oil pump. Refer to Disassembly and Assembly, "Unit Injector Hydraulic Pump - Remove".

2. Check for any physical damage to the drive gear.

3. Verify that the drive gear and the retaining bolt are properly tightened. Also verify that the pump shaft rotates freely.

Expected Result:

The drive gear and the retaining bolt for the high pressure oil pump are tight. The pump shaft rotates freely.

Results:

• OK - The drive gear bolt is properly tightened and the pump shaft rotates freely.

  Repair: Replace the high pressure oil pump. Refer to Disassembly and Assembly, "Unit Injector Hydraulic Pump - Install". Verify that the repair resolved the problem.If this does not fix the problem, contact technical support.

  STOP

• Not OK - The pump shaft does not rotate freely.

  Repair: Replace the high pressure oil pump. Refer to Disassembly and Assembly, "Unit Injector Hydraulic Pump - Install". Verify that the repair resolved the problem.If this does not fix the problem, contact technical support.

  STOP

• Not OK - The drive gear bolt is loose. The pump shaft rotates freely and there is no obvious mechanical damage that would indicate a different problem.

  Repair: Replace the drive gear, if necessary. Tighten the drive gear bolt. Refer to Specifications, "Unit Injector Hydraulic Pump". Reinstall the pump. Refer to Disassembly and Assembly, "Unit Injector Hydraulic Pump - Install". Check the pressure in order to ensure that the problem has been resolved.If this does not fix the problem, replace the high pressure oil pump. Verify that the repair has resolved the problem.

  STOP

Test Step 16. Check the High Pressure Oil System for Leaks

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Hot oil and components can cause personal injury. Do not allow hot oil or components to contact skin.

1. Remove the valve cover and inspect the high pressure oil system for oil leaks.

2. While the engine is being cranked, inspect the area around the injector bores for any signs of oil leakage. Inspect the spill ports of the injector for excessive oil. All six injectors should spill the same amount of oil.

Expected Result:

No leaks are apparent.

Results:

• OK - The high pressure oil system does not appear to be leaking.

  Repair: Call technical support for assistance.

  STOP

• Not OK - A leak has been detected in the high pressure oil system.

  Repair: Replace the O-ring on the injector or replace the damaged injector. Verify that the repair has resolved the problem.

  STOP