5230 Excavator Hydraulic System Caterpillar

Note: The troubleshooting information is intended to aid in diagnosing a given problem. The probable causes are ordered from the most probable cause to the least probable cause. The probable causes should be examined in order until the problem is resolved.

Problem: After the update to the swing system, the software appeared to download without a problem, but in Electronic Technician the machine control shows blank.

Probable Cause

1. The attachment code was not entered into VIMS.
   • Ensure the attachment code has been entered through the VIMS key pad. Refer to Service Manual, SENR6059, "Attachment Code-Configure".

Problem: The engine rpm is reduced to a near stall when the load on the hydraulic system is increased.

Probable Cause

1. The engine is not delivering full power.
   • Ensure that the engine is outputting full power. Refer to the Testing and Adjusting, "Full Load Engine Speed - Check". If the engine is not outputting full power, refer to the Electronic Troubleshooting manual or the Testing and Adjusting, "Troubleshooting" manual for the engine.

2. The Caterpillar Underspeed System is out of calibration.
   • Calibrate the Caterpillar Underspeed System. Refer to the Testing and Adjusting, "Caterpillar Underspeed System - Calibrate". If the Caterpillar Underspeed System will not calibrate, refer to "Problem: The Caterpillar Underspeed System does not calibrate".

3. The combined margin pressure is not correct.
   • Check the combined margin pressure. Refer to the Testing and Adjusting, "Combined Margin Pressure - Check".

4. The margin pressure on the implement piston pumps is out of adjustment.
   • Set the margin pressure on the implement piston pumps. Refer to the Testing and Adjusting, "Piston Pump (Implement) - Test and Adjust". If the margin pressure cannot be set on all of the pumps, refer to the "Problem: Margin pressure can not be set on all implement piston pumps". If the margin pressure cannot be set on one of the pumps, refer to the "Problem: Margin pressure can not be set on one implement piston pumps".

5. The margin relief valves are out of adjustment.
   • Set the margin relief valves. Refer to the Testing and Adjusting, "Relief Valve (Margin) - Test and Adjust".

Problem: The duty cycle is too slow.

Probable Cause

1. The machine is not properly positioned.
   • Ensure that the machine is properly positioned.

2. The truck is not properly positioned.
   • Ensure that the truck is properly positioned.

3. The bucket is overloaded.
   • Ensure that the bucket is properly loaded.

4. The swing cycle times are incorrect.
   • Check the swing cycle times. Refer to the Testing and Adjusting, "Operational Checks" for cycle times. If the swing cycle times are too slow, refer to the "Problem: The machine swings slow in both directions".

5. The implement cycle times are incorrect.
   • Check the implement cycle times. Refer to the Testing and Adjusting, "Operational Checks" for cycle times. If all of the implement circuits have slow cycle times, refer to the "Problem: The cycle times for all of the implement circuits are too slow". If one of the implement circuits has a slow cycle time, refer to the "Problem: The cycle time for one of the implement circuits is too slow".

6. There is too much cylinder drift.
   • Check the cylinder drift. Refer to the Testing and Adjusting, "Operational Checks". If there is too much cylinder drift, refer to the "Problem: There is too much drift in one of the hydraulic cylinders".

Problem: The cycle times for all of the implement circuits are too slow.

Probable Cause

1. The engine is not operating at full load speed.
   • Ensure that the engine is operating at full load speed. Refer to the Testing and Adjusting, "Full Load Engine Speed - Check". If the engine is not outputting full power, refer to the Electronic Troubleshooting manual or the Testing and Adjusting, "Troubleshooting" manual for the engine.

2. The hydraulic oil temperature is not in the normal operating range.
   • Check the hydraulic oil temperature. Refer to the Testing and Adjusting, "Hydraulic Oil Temperature - Check". If the hydraulic oil temperature is too high, refer to the "Problem: The hydraulic oil temperature is too high". If the hydraulic oil temperature is too low, refer to the "Problem: The hydraulic oil temperature is too low".

3. The pilot oil pressure is not at the correct pressure.
   • Check the pilot oil pressure at the low pressure tap on the pilot manifold. Refer to the Testing and Adjusting, "Pilot Oil Pressure - Check". If the pilot oil pressure is too high, refer to the "Problem: The pilot system pressure is too high". If the pilot oil pressure is too low, refer to the "Problem: The pilot system pressure is too low".

4. The Caterpillar Underspeed System is out of calibration.
   • Calibrate the Caterpillar Underspeed System. Refer to the Testing and Adjusting, "Caterpillar Underspeed System - Calibrate". If the Caterpillar Underspeed System will not calibrate, refer to the "Problem: The Caterpillar Underspeed System does not calibrate".

5. The margin pressure on the implement piston pumps is out of adjustment.
   • Set the margin pressure on the implement piston pumps. Refer to the Testing and Adjusting, "Piston Pump (Implement) - Test and Adjust". If the margin pressure cannot be set on all of the pumps, refer to the "Problem: The margin pressure cannot be set on all of the implement piston pumps". If the margin pressure cannot be set on one of the pumps, refer to the "Problem: The margin pressure cannot be set on one of the implement piston pumps".

6. The destroke pressure on the implement piston pumps is out of adjustment.
   • Set the destroke pressure on the implement piston pumps. Refer to the Testing and Adjusting, "Piston Pump (Implement) - Test and Adjust". If the destroke pressure cannot be set on one of the pumps, refer to the "Problem: The destroke pressure cannot be set on an implement piston pump".

7. The true load sensing signal is incorrect.
   • Check the true load sensing signal. Refer to the Testing and Adjusting, "True Load Sensing Signal - Test".

8. The margin relief valves are out of adjustment.
   • Set the margin relief valves. Refer to the Testing and Adjusting, "Relief Valve (Margin) - Test and Adjust".

Problem: The cycle time for one of the implement circuits is too slow.

Probable Cause

1. The pilot pressure at the stem of the control spool for the desired function is not correct.
   • Check pilot pressure at the stem of the desired function. Refer to the Testing and Adjusting, "Pilot Oil Pressure - Check". If the pilot pressure is not correct, inspect the lines for blockage or restriction. Inspect the implement pilot valve for proper operation.

2. The line relief valves for the affected circuit are not set correctly.
   • Adjust the line relief valves for the affected circuit. Refer to the Testing and Adjusting, "Relief Valve (Line) - Test and Adjust". If the line relief valve can not be adjusted, check the line relief valves for damage.

3. The implement control spool is damaged or the implement control spool is stuck.
   • Check the implement control spool for damage. Check the implement control spool for free movement.

4. The hydraulic cylinder piston seal is bad.
   • Inspect the piston seal on the hydraulic cylinders for the affected system. Refer to the Testing and Adjusting, "Hydraulic Cylinder - Inspect".

5. The pilot oil pressure is not at the correct pressure.
   • Check the pilot oil pressure at the low pressure tap on the pilot manifold. Refer to the Testing and Adjusting, "Pilot Oil Pressure - Check". If the pilot oil pressure is too high, refer to the "Problem: The pilot system pressure is too high". If the pilot oil pressure is too low, refer to the "Problem: The pilot system pressure is too low".

Problem: All implements are weak with the engine at full load speed (1750 rpm).

Probable Cause

1. The engine is not operating at full load speed.
   • Ensure that the engine is operating full load speed. Refer to the Testing and Adjusting, "Full Load Engine Speed - Check". If the engine is not outputting full power, refer to the Electronic Troubleshooting manual or the Testing and Adjusting, "Troubleshooting" manual for the engine.

2. The load sensing signal relief valve is not correctly set.
   • Check the load sensing signal relief valve. Refer to the Testing and Adjusting, "Relief Valve (Load Sensing Signal) - Test and Adjust". If the load sensing signal relief valve cannot be set, refer to the "Problem: The hydraulic oil temperature is too high". If the hydraulic oil temperature is too low, refer to the "Problem: The load sensing signal relief valve cannot be adjusted".

3. The margin pressure on the implement piston pumps is out of adjustment.
   • Set the margin pressure on the implement piston pumps. Refer to the Testing and Adjusting, "Piston Pump (Implement) - Test and Adjust". If the margin pressure cannot be set on all of the pumps, refer to the "Problem: The margin pressure cannot be set on all of the implement piston pumps". If the margin pressure cannot be set on one of the pumps, refer to the "Problem: The margin pressure cannot be set on one of the implement piston pumps".

4. The destroke pressure on the implement piston pumps is out of adjustment.
   • Set the destroke pressure on the implement piston pumps. Refer to the Testing and Adjusting, "Piston Pump (Implement) - Test and Adjust". If the destroke pressure cannot be set on one of the pumps, refer to the "Problem: The destroke pressure cannot be set on an implement piston pump".

5. A load signal resolver in the circuit is damaged.
   • Inspect the load signal resolvers in the circuit for damage. Refer to the Testing and Adjusting, "Shuttle Valves (Load Signal Resolver) - Inspect".

Problem: All implements and travel are slow and weak with the engine at full load speed (1750 rpm).

Probable Cause

1. The engine is not operating at full load speed.
   • Ensure that the engine is operating full load speed. Refer to the Testing and Adjusting, "Full Load Engine Speed - Check". If the engine is not outputting full power, refer to the Electronic Troubleshooting manual or the Testing and Adjusting, "Troubleshooting" manual for the engine.

2. The load sensing signal relief valve is not correctly set.
   • Check the load sensing signal relief valve. Refer to the Testing and Adjusting, "Relief Valve (Load Sensing Signal) - Test and Adjust". If the load sensing signal relief valve cannot be set, refer to the "Problem: The hydraulic oil temperature is too high". If the hydraulic oil temperature is too low, refer to the "Problem: The load sensing signal relief valve cannot be adjusted".

3. The margin relief valves are out of adjustment.
   • Set the margin relief valves. Refer to the Testing and Adjusting, "Relief Valve (Margin) - Test and Adjust".

4. The margin pressure on the implement piston pumps is out of adjustment.
   • Set the margin pressure on the implement piston pumps. Refer to the Testing and Adjusting, "Piston Pump (Implement) - Test and Adjust". If the margin pressure cannot be set on all of the pumps, refer to the "Problem: The margin pressure cannot be set on all of the implement piston pumps". If the margin pressure cannot be set on one of the pumps, refer to the "Problem: The margin pressure cannot be set on one of the implement piston pumps".

5. The destroke pressure on the implement piston pumps is out of adjustment.
   • Set the destroke pressure on the implement piston pumps. Refer to the Testing and Adjusting, "Piston Pump (Implement) - Test and Adjust". If the destroke pressure cannot be set on one of the pumps, refer to the "Problem: The destroke pressure cannot be set on an implement piston pump".

6. A load signal resolver in the circuit is damaged.
   • Inspect the load signal resolvers in the circuit for damage. Refer to the Testing and Adjusting, "Shuttle Valves (Load Signal Resolver) - Inspect".

Problem: One implement is weak with the engine at full load speed (1750 rpm).

Probable Cause

1. The engine is not operating at full load speed.
   • Ensure that the engine is operating full load speed. Refer to the Testing and Adjusting, "Full Load Engine Speed - Check". If the engine is not outputting full power, refer to the Electronic Troubleshooting manual or the Testing and Adjusting, "Troubleshooting" manual for the engine.

2. The line relief valves for the affected circuit are not set correctly.
   • Adjust the line relief valves for the affected circuit. Refer to the Testing and Adjusting, "Relief Valve (Line) - Test and Adjust". If the line relief valve can not be adjusted, check the line relief valves for damage.

3. A load signal resolver in the affected circuit is damaged.
   • Inspect the load signal resolvers in the affected circuit for damage. Refer to the Testing and Adjusting, "Shuttle Valves (Load Signal Resolver) - Inspect".

4. There is too much cylinder drift.
   • Check the cylinder drift. Refer to the Testing and Adjusting, "Operational Checks". If there is too much cylinder drift, refer to the "Problem: There is too much drift in one of the hydraulic cylinders".

Problem: All implement piston pumps are too noisy.

Probable Cause

1. There is aeration in the hydraulic oil.
   • Check for aeration in the hydraulic oil. Refer to the Testing and Adjusting, "Aeration in Oil - Check". If there is aeration in the oil, refer to the "Problem: There is a large amount of air in the hydraulic oil".

2. The margin pressure on the implement piston pumps is out of adjustment.
   • Set the margin pressure on the implement piston pumps. Refer to the Testing and Adjusting, "Piston Pump (Implement) - Test and Adjust". If the margin pressure cannot be set on all of the pumps, refer to the "Problem: The margin pressure cannot be set on all of the implement piston pumps". If the margin pressure cannot be set on one of the pumps, refer to the "Problem: The margin pressure cannot be set on one of the implement piston pumps".

3. The destroke pressure on the implement piston pumps is out of adjustment.
   • Set the destroke pressure on the implement piston pumps. Refer to the Testing and Adjusting, "Piston Pump (Implement) - Test and Adjust". If the destroke pressure cannot be set on one of the pumps, refer to the "Problem: The destroke pressure can not be set on an implement piston pump".

4. The breaker relief valve is damaged.
   • Inspect the breaker relief valve for damage. Refer to the Testing and Adjusting, "Hydraulic Tank - Inspect".

Problem: One implement piston pump is too noisy.

Probable Cause

1. The margin pressure on the implement piston pumps is out of adjustment.
   • Set the margin pressure on the implement piston pumps. Refer to the Testing and Adjusting, "Piston Pump (Implement) - Test and Adjust". If the margin pressure cannot be set on all of the pumps, refer to the "Problem: The margin pressure cannot be set on all of the implement piston pumps". If the margin pressure cannot be set on one of the pumps, refer to the "Problem: The margin pressure cannot be set on one of the implement piston pumps".

2. The destroke pressure on the implement piston pumps is out of adjustment.
   • Set the destroke pressure on the implement piston pumps. Refer to the Testing and Adjusting, "Piston Pump (Implement) - Test and Adjust". If the destroke pressure cannot be set on one of the pumps, refer to the "Problem: The destroke pressure cannot be set on an implement piston pump".

3. The breaker relief valve is damaged.
   • Inspect the breaker relief valve for damage. Refer to the Testing and Adjusting, "Hydraulic Tank - Inspect".

Problem: Modulation for all of the implement circuits are not normal.

Probable Cause

1. The hydraulic oil temperature is not in the normal operating range.
   • Check the hydraulic oil temperature. Refer to the Testing and Adjusting, "Hydraulic Oil Temperature - Check". If the hydraulic oil temperature is too high, refer to the "Problem: The hydraulic oil temperature is too high". If the hydraulic oil temperature is too low, refer to the "Problem: The hydraulic oil temperature is too low".

2. There is aeration in the hydraulic oil.
   • Check for aeration in the hydraulic oil. Refer to the Testing and Adjusting, "Aeration in Oil - Check". If there is aeration in the oil, refer to the "Problem: There is a large amount of air in the hydraulic oil".

3. The pilot oil pressure is not at the correct pressure.
   • Adjust the low pressure pilot relief valve. Refer to the Testing and Adjusting, "Relief Valve (Pilot) - Test and Adjust". If the low pressure pilot relief valve cannot be set, purge the air from the ends of the implement control valves at the end housings. Refer to the Testing and Adjusting, "Control Valve End Housings - Purge". If the low pressure pilot relief valve can be set, set the high pressure pilot relief valve. Refer to the Testing and Adjusting, "Relief Valve (Pilot) - Test and Adjust".

Problem: Modulation for one of the implement circuits is not normal.

Probable Cause

1. There is air in the control valve end housing for the affected circuit.
   • Purge the control valve end housing of the affected circuit. Refer to the Testing and Adjusting, "Control Valve End Housings - Purge".

2. The pilot valve is not operating properly.
   • Inspect the valve plate, the spool, and the springs in the affected pilot valve.

3. The implement control spool is damaged or the implement control spool is stuck.
   • Check the implement control spool for damage. Check the implement control spool for free movement.

4. A load signal resolver in the affected circuit is damaged.
   • Inspect the load signal resolvers in the affected circuit for damage. Refer to the Testing and Adjusting, "Shuttle Valves (Load Signal Resolver) - Inspect".

Problem: There is too much drift in one of the hydraulic cylinders.

Probable Cause

Note: Before troubleshooting the problem, verify that the cylinder drift is out of specification. Refer to the Testing and Adjusting, "Operational Checks".

1. The hydraulic cylinder piston seal is bad.
   • Inspect the piston seal on the hydraulic cylinders for the affected system. Refer to the Testing and Adjusting, "Hydraulic Cylinder - Inspect".

2. The line relief valve for the affected circuit is damaged or the seat for the line relief valve is damaged.
   • Remove the line relief valve and inspect the line relief valve for damage. Inspect the valve seat for the line relief valve.

3. The implement makeup valve for the affected circuit is damaged or the seat for the implement makeup valve is damaged.
   • Remove the implement makeup valve and inspect the implement makeup valve for damage. Inspect the valve seat for the implement makeup valve.

Problem: The hydraulics are jerky.

Probable Cause

1. The pilot oil pressure is not at the correct pressure.
   • Check the pilot oil pressure at the low pressure tap on the pilot manifold. Refer to the Testing and Adjusting, "Pilot Oil Pressure - Check". If the pilot oil pressure is too high, refer to the "Problem: The pilot system pressure is too high". If the pilot oil pressure is too low, refer to the "Problem: The pilot system pressure is too low".

2. The Caterpillar Underspeed System is out of calibration.
   • Calibrate the Caterpillar Underspeed System. Refer to the Testing and Adjusting, "Caterpillar Underspeed System - Calibrate". If the Caterpillar Underspeed System will not calibrate, refer to the "Problem: The Caterpillar Underspeed System does not calibrate".

3. The margin pressure on the implement piston pumps is out of adjustment.
   • Set the margin pressure on the implement piston pumps. Refer to the Testing and Adjusting, "Piston Pump (Implement) - Test and Adjust". If the margin pressure cannot be set on all of the pumps, refer to the "Problem: The margin pressure cannot be set on all of the implement piston pumps". If the margin pressure cannot be set on one of the pumps, refer to the "Problem: The margin pressure cannot be set on one of the implement piston pumps".

4. The destroke pressure on the implement piston pumps is out of adjustment.
   • Set the destroke pressure on the implement piston pumps. Refer to the Testing and Adjusting, "Piston Pump (Implement) - Test and Adjust". If the destroke pressure cannot be set on one of the pumps, refer to the "Problem: The destroke pressure cannot be set on an implement piston pumps".

5. The line relief valves for the affected circuits are not set correctly.
   • Adjust the line relief valves for the affected circuits. Refer to the Testing and Adjusting, "Relief Valve (Line) - Test and Adjust". If the line relief valve cannot be adjusted, check the line relief valves for damage.

6. The line relief valves for the other circuits are not set correctly.
   • Adjust the line relief valves for the other circuits. Refer to the Testing and Adjusting, "Relief Valve (Line) - Test and Adjust". If the line relief valve cannot be adjusted, check the line relief valves for damage.

Problem: The bucket clam is slow during bucket bottom dump.

Probable Cause

1. The line relief valves for the bucket bottom dump circuit are not set correctly.
   • Adjust the line relief valves for the bucket bottom dump circuit. Refer to the Testing and Adjusting, "Relief Valve (Line) - Test and Adjust". If the line relief valve cannot be adjusted, check the line relief valves for damage.

2. The hydraulic cylinders for the bucket clam are damaged.
   • Inspect the hydraulic cylinders for damage. Refer to the Testing and Adjusting, "Hydraulic Cylinder - Inspect".

Problem: The bucket clam does not open properly.

Probable Cause

1. The hydraulic cylinders for the bucket clam are damaged.
   • Inspect the hydraulic cylinders for damage. Refer to the Testing and Adjusting, "Hydraulic Cylinder - Inspect".

Problem: Boom up is slow until another implement is actuated.

Probable Cause

1. The line relief valves for the boom circuit are not set correctly.
   • Adjust the line relief valves for the boom circuit. Refer to the Testing and Adjusting, "Relief Valve (Line) - Test and Adjust". If the line relief valve cannot be adjusted, check the line relief valves for damage.

2. A load signal resolver in the boom circuit is damaged.
   • Inspect the load signal resolvers in the boom circuit for damage. Refer to the Testing and Adjusting, "Shuttle Valves (Load Signal Resolver) - Inspect".

Note: If the problem gets progressively worse above 43 °C (110 °F) perform the next step.

3. The true load sensing signal is incorrect.
   • Check the true load sensing signal. Refer to the Testing and Adjusting, "True Load Sensing Signal - Test".

Problem: The implement surges when the implement is actuated.

Probable Cause

1. The pilot oil pressure is not at the correct pressure.
   • Check the pilot oil pressure at the low pressure tap on the pilot manifold. Refer to the Testing and Adjusting, "Pilot Oil Pressure - Check". If the pilot oil pressure is too high, refer to the "Problem: The pilot system pressure is too high". If the pilot oil pressure is too low, refer to the "Problem: The pilot system pressure is too low".

2. The pilot pressure at the stem of the control spool for the desired function is not modulating.
   • Check the pilot pressure at the stem of the desired function while you modulate the pilot valve. Refer to the Testing and Adjusting, "Pilot Oil Pressure - Check". If the pilot pressure does not modulate, inspect the lines for blockage or restriction. Inspect the implement pilot valve for proper operation.

3. The springs for the implement control spool are damaged.
   • Check the springs for the implement control spool for damage.

4. The implement control spool is damaged or the implement control spool is stuck.
   • Check the implement control spool for damage. Check the implement control spool for free movement.

5. The margin pressure on the implement piston pumps is out of adjustment.
   • Set the margin pressure on the implement piston pumps. Refer to the Testing and Adjusting, "Piston Pump (Implement) - Test and Adjust". If the margin pressure cannot be set on all of the pumps, refer to the "Problem: The margin pressure cannot be set on all of the implement piston pumps". If the margin pressure cannot be set on one of the pumps, refer to the "Problem: The margin pressure cannot be set on one of the implement piston pumps".

6. The destroke pressure on the implement piston pumps is out of adjustment.
   • Set the destroke pressure on the implement piston pumps. Refer to the Testing and Adjusting, "Piston Pump (Implement) - Test and Adjust". If the destroke pressure cannot be set on one of the pumps, refer to the "Problem: The destroke pressure cannot be set on an implement piston pump".

7. The margin relief valves are out of adjustment.
   • Set the margin relief valves. Refer to the Testing and Adjusting, "Relief Valve (Margin) - Test and Adjust".

Problem: The boom hesitates after the stick stalls or after the bucket stalls.

Probable Cause

1. The engine is not operating at full load speed.
   • Ensure that the engine is operating full load speed. Refer to the Testing and Adjusting, "Full Load Engine Speed - Check". If the engine is not outputting full power, refer to the Electronic Troubleshooting manual or the Testing and Adjusting, "Troubleshooting" manual for the engine.

2. The hydraulic oil temperature is not in the normal operating range.
   • Check the hydraulic oil temperature. Refer to the Testing and Adjusting, "Hydraulic Oil Temperature - Check". If the hydraulic oil temperature is too high, refer to the "Problem: The hydraulic oil temperature is too high". If the hydraulic oil temperature is too low, refer to the "Problem: The hydraulic oil temperature is too low".

3. The pilot oil pressure is not at the correct pressure.
   • Check the pilot oil pressure at the low pressure tap on the pilot manifold. Refer to the Testing and Adjusting, "Pilot Oil Pressure - Check". If the pilot oil pressure is too high, refer to the "Problem: The pilot system pressure is too high". If the pilot oil pressure is too low, refer to the "Problem: The pilot system pressure is too low".

4. The Caterpillar Underspeed System is out of calibration.
   • Calibrate the Caterpillar Underspeed System. Refer to the Testing and Adjusting, "Caterpillar Underspeed System - Calibrate". If the Caterpillar Underspeed System will not calibrate, refer to the "Problem: The Caterpillar Underspeed System does not calibrate".

5. The margin pressure on the implement piston pumps is out of adjustment.
   • Set the margin pressure on the implement piston pumps. Refer to the Testing and Adjusting, "Piston Pump (Implement) - Test and Adjust". If the margin pressure cannot be set on all of the pumps, refer to the "Problem: The margin pressure cannot be set on all of the implement piston pumps". If the margin pressure cannot be set on one of the pumps, refer to the "Problem: The margin pressure cannot be set on one of the implement piston pumps".

6. The destroke pressure on the implement piston pumps is out of adjustment.
   • Set the destroke pressure on the implement piston pumps. Refer to the Testing and Adjusting, "Piston Pump (Implement) - Test and Adjust". If the destroke pressure cannot be set on one of the pumps, refer to the "Problem: The destroke pressure cannot be set on an implement piston pump".

7. The true load sensing signal is incorrect.
   • Check the true load sensing signal. Refer to the Testing and Adjusting, "True Load Sensing Signal - Test".

8. The margin relief valves are out of adjustment.
   • Set the margin relief valves. Refer to the Testing and Adjusting, "Relief Valve (Margin) - Test and Adjust".

9. The 124-1400 Signal Duplication Valve is not installed.
   • Remove the signal duplication valve from the front control valve and verify that the part number is 124-1400 .

Problem: The machine will not travel when the levers or the pedals are actuated.

Probable Cause

1. There are obstacles that are preventing the machine from moving.
   • Check for obstacles in the path of the machine.

2. The hydraulic activation control lever is not in the engaged position.
   • Verify that the hydraulic activation control lever is in the correct position in order to operate the machine. Refer to the Operation and Maintenance Manual for the operating position of the hydraulic activation control lever.

3. The ladder is not raised.
   • Check the position of the ladder in the Vital Information Management System (VIMS). Refer to the Testing and Adjusting, "Ladder Position - Check". If the VIMS does not indicate that the ladder is raised, visually inspect the position of the ladder. If the ladder is raised and the VIMS indicates that the ladder is down, the position of the ladder position switch should be checked. Refer to the Testing and Adjusting, "Position Switch (Ladder) - Check and Adjust".

4. The travel parking brakes are not being released.
   • Check the brake release pressure for the travel parking brakes at the swivel. Refer to the Testing and Adjusting, "Pressure for Travel Parking Brake Release - Check". If the parking brake release pressure at the swivel is within specifications proceed to Step 12. If the parking brake release pressure at the swivel is not within specifications proceed to the next step.

5. The pilot oil pressure is not at the correct pressure.
   • Check the pilot oil pressure at the low pressure tap on the pilot manifold. Refer to the Testing and Adjusting, "Pilot Oil Pressure - Check". If the pilot oil pressure is too high, refer to the "Problem: The pilot system pressure is too high". If the pilot oil pressure is too low, refer to the "Problem: The pilot system pressure is too low".

6. The implement functions do not operate.
   • Operate the implement functions. If the implement functions do not operate properly, check the hydraulic activation control selector valve for damage.

7. The pilot oil pressure at the pilot manifold for the release of the travel parking brakes is incorrect.
   • Check the brake release pressure for the travel parking brakes at the pilot manifold. Refer to the Testing and Adjusting, "Pressure for Travel Parking Brake Release - Check". If the parking brake release pressure at the pilot manifold is not within specifications proceed to Step 9. If the parking brake release pressure at the manifold is within specifications proceed to the next step.

8. The electrical signal to the ladder position solenoid is incorrect.
   • Check the signal to the ladder position solenoid. If the signal is incorrect, troubleshoot the electrical system. If the signal is correct, replace the ladder position solenoid.

9. The pilot pressure from the resolver manifold to the travel parking brake dual pressure control valve is incorrect.
   • Check the pilot pressure from the resolver manifold to the travel parking brake dual pressure control valve. Refer to the Testing and Adjusting, "Pressure for Travel Parking Brake Release - Check". If the pilot pressure is at least 2654 kPa (385 psi), replace the travel parking brake dual pressure control valve. If the pilot pressure is less than 2654 kPa (385 psi), inspect the resolver valves in the pilot manifold for damage. Refer to the Testing and Adjusting, "Shuttle Valves (Pilot Resolver) - Inspect".

10. The travel pilot valve is damaged.
    • Inspect the travel pilot valve for damage.

11. There is a restriction or there is a blockage in one of the lines for brake release pressure for the travel parking brakes.
    • Inspect the line for restrictions or for blockage.

12. The pilot pressure to the control valve stems in the rear control valve is not present.
    • Check the pilot pressure at the control valve stems for the travel functions. Refer to the Testing and Adjusting, "Pilot Oil Pressure - Check". If the pilot pressure at the stem is present, proceed to Step 14. If the pilot pressure at the stem is not present, proceed to the next step.

13. The pilot pressure at the cab support for the control valve stems is not present.
    • Check the pilot pressure at the cab support for the travel functions. Refer to the Testing and Adjusting, "Pilot Oil Pressure - Check". If the pilot pressure at the cab support is not present, check for restricted lines between the cab support and the pilot manifold. If the pilot pressure at the cab support is present, check for restricted lines between the cab support and the rear control valve.

14. A load signal resolver in the front control valve is damaged.
    • Cycle the bucket and stall the bucket. While you hold the bucket at a stall condition, actuate the travel pilot valve. If the machine travels, inspect the load signal resolvers in the front control valve for damage. Refer to the Testing and Adjusting, "Shuttle Valves (Load Signal Resolver) - Inspect".

15. If the machine is a front shovel, the main resolver valve in the rear control valve is damaged.
    • Actuate the bucket bottom dump. If the bucket does not actuate, inspect the main resolver valve in the rear control valve for damage. Refer to the Testing and Adjusting, "Shuttle Valves (Load Signal Resolver) - Inspect".

16. A resolver valve in the rear control valve is damaged.
    • Inspect the resolver valves in the rear control valve for damage. Refer to the Testing and Adjusting, "Shuttle Valves (Load Signal Resolver) - Inspect".

17. The main system pressure at the implement high pressure screens is incorrect.
    • Check the main system pressure at the implement high pressure screens. Refer to the Testing and Adjusting, "Main System Pressure - Check". If the pressure is less than 30000 kPa (4350 psi), proceed to Step 20. If the pressure is at least than 30000 kPa (4350 psi), proceed to the next step.

18. The routing of the lines is incorrect.
    • Check the routing of the lines if the travel motors have been recently repaired.

19. The travel parking brakes are damaged.
    • Inspect the travel parking brakes for damage and for proper operation.

20. The line relief valves are not set correctly.
    • Test and adjust the line relief valves. Refer to the Testing and Adjusting, "Relief Valve (Line) - Test and Adjust". If the line relief valve can not be adjusted, check the line relief valves for damage.

21. The swivel is damaged.
    • Test the swivel in order to determine if the swivel is bad. Refer to the Testing and Adjusting, "Swivel - Test".

Problem: The machine travels slow in both directions.

Probable Cause

1. The pilot oil pressure is not at the correct pressure.
   • Check the pilot oil pressure at the low pressure tap on the pilot manifold. Refer to the Testing and Adjusting, "Pilot Oil Pressure - Check". If the pilot oil pressure is not at least 3100 kPa (450 psi), refer to the "Problem: The pilot system pressure is too low". Also, inspect the swing brakes and the travel brakes for damage.

2. The pilot oil pressure at the travel control spools in the rear control valve is not correct.
   • Check the pilot oil pressure at the control spools in the rear control valve. Refer to the Testing and Adjusting, "Pilot Oil Pressure - Check". If the pilot oil pressure is not at least 3100 kPa (450 psi), inspect the travel pilot valve for damage.

3. The main system pressure is not correct when the machine is stalled.
   • Check the main system pressure at the implement high pressure screens. Refer to the Testing and Adjusting, "Main System Pressure - Check". If the main system pressure is not at least 35000 kPa (5075 psi), adjust the load sensing signal relief valve. Refer to the Testing and Adjusting, "Relief Valve (Load Sensing Signal) - Test and Adjust". If the load sensing signal relief valve cannot be set, refer to the "Problem: The load sensing signal relief valve cannot be adjusted".

4. The main system pressure is not correct when the machine is moving.
   • Check the main system pressure at the implement high pressure screens. Perform the Testing and Adjusting, "Main System Pressure - Check". Ensure that the travel parking brakes are released during the test. The machine will move. If the main system pressure is at least 30000 kPa (4350 psi), inspect the travel parking brakes for damage. If the main system pressure is not at least 30000 kPa (4350 psi), proceed to the next step.

5. The travel circuit pressure at the counterbalance valve is not correct when the machine is stalled.
   • Check the travel circuit pressure at the counterbalance valve. Refer to the Testing and Adjusting, "Circuit Pressure - Check". If the travel circuit pressure is not at least 35000 kPa (5075 psi), proceed to Step 11. If the travel circuit pressure is at least 35000 kPa (5075 psi), proceed to the next step.

6. The case drain pressure at the swivel is high.
   • Check the case drain pressure at the swivel. Refer to the Testing and Adjusting, "Case Drain - Test". If the case drain pressure is above 103 kPa (15 psi), proceed to Step 9. If the case drain pressure is not above 103 kPa (15 psi), proceed to the next step.

7. There is leakage across the ports of the travel motor.
   • Check the travel motors for leakage across the ports. Refer to the Testing and Adjusting, "Travel Motor (Cross Port Leak) - Test".

8. The swivel is damaged.
   • Test the swivel in order to determine if the swivel is bad. Refer to the Testing and Adjusting, "Swivel - Test".

9. The case drain pressure at a travel motor is high.
   • Check the case drain for the travel motors. Refer to the Testing and Adjusting, "Case Drain - Test".

10. The swivel is damaged.
    • Test the swivel in order to determine if the swivel is bad. Refer to the Testing and Adjusting, "Swivel - Test".

11. The margin pressure on the implement piston pumps is out of adjustment.
    • Set the margin pressure on the implement piston pumps. Refer to the Testing and Adjusting, "Piston Pump (Implement) - Test and Adjust". If the margin pressure cannot be set on all of the pumps, refer to the "Problem: The margin pressure cannot be set on all of the implement piston pumps". If the margin pressure cannot be set on one of the pumps, refer to the "Problem: The margin pressure cannot be set on one of the implement piston pumps".

12. The destroke pressure on the implement piston pumps is out of adjustment.
    • Set the destroke pressure on the implement piston pumps. Refer to the Testing and Adjusting, "Piston Pump (Implement) - Test and Adjust". If the destroke pressure cannot be set on one of the pumps, refer to the "Problem: The destroke pressure cannot be set on an implement piston pump".

13. An implement pump is bad.
    • Test the case drain on the implement piston pumps. Refer to the Testing and Adjusting, "Case Drain - Test".

Problem: The machine travels slow in one directions.

Probable Cause

1. The pilot oil pressure at the travel control spools in the rear control valve is not correct.
   • Check the pilot oil pressure at the control spools in the rear control valve. Refer to the Testing and Adjusting, "Pilot Oil Pressure - Check". If the pilot oil pressure is not at least 3100 kPa (450 psi), inspect the pilot valve for damage. If the pilot oil pressure is at least 3100 kPa (450 psi), adjust the line relief valves for travel. Refer to the Testing and Adjusting, "Relief Valve (Line) - Test and Adjust".

2. The case drain pressure at a travel motor is high.
   • Check the case drain for the travel motors. Refer to the Testing and Adjusting, "Case Drain - Test".

Problem: The machine travels on one side only.

Probable Cause

1. The pilot oil pressure at the travel control spools in the rear control valve is not correct.
   • Check the pilot oil pressure at the control spools in the rear control valve. Refer to the Testing and Adjusting, "Pilot Oil Pressure - Check". If the pilot oil pressure is not at least 3100 kPa (450 psi), inspect the travel pilot valve for damage.

2. The brake release pressure for the travel parking brakes at the travel motors on the affected side is too low.
   • Check the brake release pressure for the travel parking brakes at the travel motors on the affected side. Refer to the Testing and Adjusting, "Pressure for Travel Parking Brake Release - Check". If the pilot oil pressure is not at least 3100 kPa (450 psi) at low idle, check for restrictions in the line between the swivel and the travel parking brake.

3. The pressure is not correct in the travel circuit when the machine is moving.
   • Check the pressure in the travel circuit at the rear control valve on the affected side. Perform the Testing and Adjusting, "Circuit Pressure - Check". Ensure that the travel parking brakes are released during the test. The machine will move. If the pressure in the travel circuit is not at least 20000 kPa (2900 psi), proceed to Step 5. If the main system pressure is at least 20000 kPa (2900 psi), proceed to the next step.

4. The main system pressure is not correct when the machine is stalled.
   • Check the main system pressure at the implement high pressure screens. Refer to the Testing and Adjusting, "Main System Pressure - Check". If the main system pressure is not at least 35000 kPa (5075 psi), adjust the travel line relief valves. Refer to the Testing and Adjusting, "Relief Valve (Line) - Test and Adjust". If the main system pressure is at least 35000 kPa (5075 psi), inspect the travel parking brakes on the affected side for damage.

5. The swivel is damaged.
   • If the track on the left side is affected, test the swivel. Refer to the Testing and Adjusting, "Swivel - Test".

Problem: The machine veers to the right or the machine veers to the left.

Probable Cause

1. There is too much drift in the travel circuit.
   • Check the drift in the travel circuit. Refer to the Testing and Adjusting, "Operational Checks". If the drift in the travel circuit is out of specification, proceed to the next step.

2. The pilot oil pressure is not at the correct pressure.
   • Check the pilot oil pressure at the low pressure tap on the pilot manifold. Refer to the Testing and Adjusting, "Pilot Oil Pressure - Check". If the pilot oil pressure is not at least 3100 kPa (450 psi), refer to the "Problem: The pilot system pressure is too low". Also, inspect the swing brakes and the travel brakes for damage.

3. The travel parking brake on the slow side is not fully released.
   • Check the brake release pressure for the travel parking brakes at the travel motors on the slow side. Refer to the Testing and Adjusting, "Pressure for Travel Parking Brake Release - Check". If the pilot oil pressure is not at least 3100 kPa (450 psi) at low idle, check for restrictions in the line between the swivel and the travel parking brake.

4. There is a bad motor on the slow side.
   • Check the case drain for the travel motors on the slow side. Refer to the Testing and Adjusting, "Case Drain - Test".

5. The circuit pressure for travel is different on both sides of the machine.
   • Check the circuit pressure for travel for both sides of the machine at the rear control valve. Refer to the Testing and Adjusting, "Circuit Pressure - Check". If the circuit pressure on the slow side is greater than the other side, inspect the travel parking brakes on the affected side for damage.

6. The line relief valves for travel on the slow side are not set correctly.
   • Adjust the line relief valves for the slow side. Refer to the Testing and Adjusting, "Relief Valve (Line) - Test and Adjust". If the line relief valves can not be adjusted, test the swivel for damage. Refer to the Testing and Adjusting, "Swivel - Test".

7. The travel counterbalance valve is not operating properly.
   • Inspect the spools in the travel counterbalance valve for free movement.

8. The rear control valve is damaged.
   • Check the control spools in the rear control valve for free movement. Ensure that the proper number of shims are installed.

9. The swivel is damaged.
   • Test the swivel in order to determine if the swivel is bad. Refer to the Testing and Adjusting, "Swivel - Test".

Problem: The machine will not pivot.

Probable Cause

Note: If the machine does not travel in a straight line, refer to the "Problem: The machine veers to the right or the machine veers to the left".

1. Resolver valves in the resolver manifold are damaged.
   • Inspect the resolver valves in the pilot manifold for damage. Refer to the Testing and Adjusting, "Shuttle Valves (Pilot Resolver) - Inspect".

2. A load signal resolver valve in the rear control valve is damaged.
   • Inspect the load signal resolver valves in the rear control valve for damage. Refer to the Testing and Adjusting, "Shuttle Valves (Load Signal Resolver) - Inspect".

Problem: The machine will not swing.

Probable Cause

1. No other implements operate.
   • Actuate the other implements. If none of the implements operate, check the position of the hydraulic activation control selector valve. If the hydraulic activation control selector valve is not in the operating position move the valve to the operating position.

2. The pilot oil pressure is not at the correct pressure.
   • Check the pilot oil pressure at the low pressure tap on the pilot manifold. Refer to the Testing and Adjusting, "Pilot Oil Pressure - Check". If the pilot oil pressure is not within specification, refer to the "Problem: The pilot system pressure is too low".

3. The ladder is not raised.
   • Check the position of the ladder in the Vital Information Management System (VIMS). Refer to the Testing and Adjusting, "Ladder Position - Check". If the VIMS does not indicate that the ladder is raised, visually inspect the position of the ladder. If the ladder is raised and the VIMS indicates that the ladder is down, check the position switch for the ladder. Refer to the Testing and Adjusting, "Position Switch (Ladder) - Check and Adjust".

4. The solenoid valve for the swing parking brakes is not electrically connected.
   • Visually inspect the electrical connection for the solenoid valve for swing parking brakes.

5. The swing system pressure is not correct.
   • Check the swing system pressure while you are shifting the swing pilot control lever. Refer to the Testing and Adjusting, "Swing System Pressure - Check". If the swing system pressure is not above 35000 kPa (5080 psi) proceed to Step 10. If the swing system pressure is above 35000 kPa (5080 psi) proceed to the next step.

6. There is no brake release pressure to the swing parking brakes.
   • Check the brake release pressure to the swing parking brakes. Refer to the Testing and Adjusting, "Pressure for Swing Parking Brake Release - Check". If there is no brake release pressure to the swing parking brakes, proceed to Step 8. If the brake release pressure to the swing parking brakes is correct, proceed to the next step.

7. There is an obstruction in the swing gear.
   • Check the swing gear for obstructions. If there is no obstruction, proceed to the next step. If there is an obstruction remove the obstruction. If the machine will not swing, check the swing gear and the swing drive pinions for damage.

8. The solenoid valve for the swing parking brakes is not receiving the correct electrical signal.
   • Check the solenoid valve for the swing parking brakes for an electrical signal while you actuate the swing function. If the signal is not correct, troubleshoot the electrical system.

9. The solenoid valve for the swing parking brakes is damaged.
   • Check the solenoid valve for the swing parking brake for proper operation.

10. The pilot pressure to the swing control valve is incorrect.
    • Check the pilot pressure at both stems of the swing control valve while you stall the swing left and the swing right. Refer to the Testing and Adjusting, "Pilot Oil Pressure - Check". If the pilot oil pressure at the stems is 4000 kPa (580 psi) on the actuated side and 0 kPa (0 psi) on the stem that is not actuated proceed to Step 12. If the pilot oil pressure at the stems is 4000 kPa (580 psi) on both sides or 0 kPa (0 psi) on both sides at the same time, replace the swing pilot valve.

11. There is a restriction in the pilot lines to the ends of the swing control valve.
    • Inspect the pilot lines to the swing control valve for blockage and for restrictions.

12. The swing dual pressure relief valve is not set correctly.
    • Check the pressure setting of the swing dual pressure relief valve. Refer to the Testing and Adjusting, "Relief Valve (Swing Dual Pressure) - Test and Adjust". If the swing dual pressure relief valve cannot be adjusted, refer to the "Problem: The swing dual pressure relief valve cannot be adjusted".

13. A swing motor is bad.
    • Rapidly shift the swing pilot control lever in one direction to full swing. Observe the case drain lines for the swing motors. If any of the case drain lines jump, perform the swing motor case drain test. Refer to the Testing and Adjusting, "Case Drain - Test".

14. The swing crossover relief valve is damaged.
    • Inspect the swing crossover relief valve for damage. Inspect makeup valves, check valves, and 104-5030 Relief Valve. Check all seals and sealing surfaces for damage. Check all seats and seating surfaces for damage.

15. Springs in the swing control valve are damaged.
    • Remove the end caps from the swing control valve. Inspect the springs at the ends of the control spool for damage.

16. The control spool in the swing control valve is damaged or movement is restricted.

    Note: It is not necessary to fully remove the control spool from the valve body for inspection. Remove 75% of the spool from the valve body for inspection.

    • Inspect the spool for damage and for free movement.

17. The swing pressure relief valve is damaged.
    • Inspect the swing pressure relief valve for damage.

Problem: The machine swings normally in one direction and slow or not at all in the other direction.

Probable Cause

1. The pilot pressure to the swing control valve is incorrect.
   • Check the pilot pressure at both stems of the swing control valve while you stall the swing left and the swing right. Refer to the Testing and Adjusting, "Pilot Oil Pressure - Check". If the pilot oil pressure at the stems is 4000 kPa (580 psi) on the actuated side and 0 kPa (0 psi) on the stem that is not actuated proceed to the next step. If the pilot oil pressure at the stems is less than 4000 kPa (580 psi) on one side or 0 kPa (0 psi) on both sides at the same time, inspect the travel pilot valve for damage.

2. The swing crossover relief valve is damaged.
   • Inspect the swing crossover relief valve for damage. Inspect makeup valves, check valves, and 104-5030 Relief Valve. Check all seals and sealing surfaces for damage. Check all seats and seating surfaces for damage.

3. Springs in the swing control valve are damaged.
   • Remove the end caps from the swing control valve. Inspect the springs at the ends of the control spool for damage.

4. The control spool in the swing control valve is damaged or movement is restricted.

   Note: It is not necessary to fully remove the control spool from the valve body for inspection. Remove 75% of the spool from the valve body for inspection.

   • Inspect the spool for damage and for free movement.

Problem: The machine starts to swing, but slows down almost to a stop.

Probable Cause

1. The 6T-6552 Valve Manifold is probably installed upside down.
   • Make sure the left hand mounting bolt is facing the front of the machine, and the solenoid valve is pointing to the rear of the machine. If the manifold is not mounted correctly it will be necessary to reposition the 183-6273 Block that the valve manifold mounts to. Refer to Special Instruction, REHS0952, "Installation of the Pressure Reducing Valve for the 5230 Excavator"

Problem: The swing cycle time is very slow.

Probable Cause

1. The 6T-6552 Valve Manifold is probably installed upside down.
   • Make sure the left hand mounting bolt is facing the front of the machine, and the solenoid valve is pointing to the rear of the machine. If the manifold is not mounted correctly it will be necessary to reposition the 183-6273 Block that the valve manifold mounts to. Refer to Special Instruction, REHS0952, "Installation of the Pressure Reducing Valve for the 5230 Excavator"

2. Air is trapped in the swing signal line.
   • Throughly purge the swing signal line that connects the swing control valve to the swing pump compensator.

3. The shuttle valve in the pilot lines for the swing brakes is bad.
   • Remove the 198-4707 Shuttle Valve and test to see if swing times improve. If swing time improves substantially, replace the shuttle valve with a new shuttle valve.

Problem: The machine swings slow in both directions.

Probable Cause

1. The pilot pressure to the swing control valve is incorrect.
   • Check the pilot pressure at both stems of the swing control valve while you stall the swing left and the swing right. Refer to the Testing and Adjusting, "Pilot Oil Pressure - Check". If the pilot oil pressure at the stems is 4000 kPa (580 psi) on the actuated side and 0 kPa (0 psi) on the stem that is not actuated, proceed to Step 3. If the pilot oil pressure at the stems is not 4000 kPa (580 psi) on the actuated side and 0 kPa (0 psi) on the stem that is not actuated, proceed to the next step.

2. The pilot oil pressure is not at the correct pressure.
   • Check the pilot oil pressure at the low pressure tap on the pilot manifold. Refer to the Testing and Adjusting, "Pilot Oil Pressure - Check". If the pilot oil pressure is not within specification, refer to the "Problem: The pilot system pressure is too low".

3. The swing system pressure is not correct.
   • Check the swing system pressure. Refer to the Testing and Adjusting, "Swing System Pressure - Check". If the swing system pressure is not 35000 kPa (5075 psi), proceed to the next step. If the swing system pressure is 35000 kPa (5075 psi), set the destroke on the swing piston pumps. Refer to the Testing and Adjusting, "Piston Pump (Swing) - Test and Adjust".

4. The high pressure setting on the swing dual pressure relief valve is incorrect.
   • Check the swing dual pressure relief valve. Refer to the Testing and Adjusting, "Relief Valve (Swing Dual Pressure) - Test and Adjust". If the high pressure setting of the swing dual pressure relief valve cannot be set at 35000 kPa (5075 psi), refer to the "Problem: The swing dual pressure relief valve cannot be adjusted".

5. The swing crossover relief valve is damaged.
   • Inspect the swing crossover relief valve for damage. Inspect makeup valves, check valves, and 104-5030 Relief Valve. Check all seals and sealing surfaces for damage. Check all seats and seating surfaces for damage.

The machine free swings when the swing pilot lever is returned to neutral after swinging.

Probable Cause

1. A swing motor is bad.
   • Rapidly shift the swing pilot control lever in one direction to full swing. Observe the case drain lines for the swing motors. If any of the case drain lines jump, perform the swing motor case drain test. Refer to the Testing and Adjusting, "Case Drain - Test".

The machine vibrates when the machine swings.

Probable Cause

Note: If the vibration occurs during deceleration, proceed to Step 1. If the vibration occurs during acceleration, proceed to Step 6.

1. A swing motor is bad.
   • Rapidly shift the swing pilot control lever in one direction to full swing. Observe the case drain lines for the swing motors. If any of the case drain lines jump, perform the swing motor case drain test. Refer to the Testing and Adjusting, "Case Drain - Test".

2. The deceleration setting of the swing dual pressure relief valve is incorrect.
   • Check the deceleration setting of the swing dual pressure relief valve. Refer to the Testing and Adjusting, "Relief Valve (Swing Dual Pressure) - Test and Adjust".

3. The swing dual pressure relief valve is unstable.
   • Check for instability in the swing dual pressure relief valve. Refer to the Testing and Adjusting, "Relief Valve (Swing Dual Pressure) Instability - Test". If the swing dual pressure relief valve is unstable, refer to the "Problem: Instability in the swing dual pressure relief valve".

4. 128-3689 Orifice Plate is not installed in the main return line for the swing system.
   • Verify that the 128-3689 Orifice Plate is installed in the 6I-7627 Return Lines .

5. There is damage in the swing crossover relief valve.
   • Inspect the makeup valves and the check valves in the swing crossover relief valve for damage.

6. The acceleration setting of the swing dual pressure relief valve is incorrect.
   • Check the acceleration setting of the swing dual pressure relief valve. Refer to the Testing and Adjusting, "Relief Valve (Swing Dual Pressure) - Test and Adjust".

7. The swing dual pressure relief valve is unstable.
   • Check for instability in the swing dual pressure relief valve. Refer to the Testing and Adjusting, "Relief Valve (Swing Dual Pressure) Instability - Test". If the swing dual pressure relief valve is unstable, refer to the "Problem: Instability in the swing dual pressure relief valve".

8. The swing drives are misaligned with the swing gear.
   • Check for misalignment of the swing drives to the swing gear.

9. The swing gear or the swing drive pinions have broken teeth.
   • Check for broken teeth on the swing gear and the swing drive pinions.

10. The bolts that attach the swing drives are loose.
    • Check the swing drives for loose bolts.

Problem: After the update to the swing system, there is an annoying hydraulic noise in or under the cab that wasn't there before.

Probable Cause

1. A dirty or damaged pressure reducing valve for the low pilot.
   • Remove and clean the pressure reducing valve for the low pilot, reinstall the pressure reducing valve for the low pilot, torque the valve to 80 N·m (60 lb ft), and set pilot pressures. If the noise persists, replace the pressure reducing valve for the low pilot.

Problem: The pilot system pressure is too low.

Probable Cause

1. The low pressure pilot relief valve is set incorrectly.
   • Check the low pressure pilot relief valve. Refer to the Testing and Adjusting, "Relief Valve (Pilot) - Test and Adjust". If the low pressure pilot relief valve can be adjusted, adjust the high pressure pilot relief valve. If the low pressure pilot relief valve cannot be adjusted, inspect the low pressure pilot relief valve. If the relief valve is damaged replace the valve and adjust both the high pressure pilot relief valve and the low pressure pilot relief valve.

2. The pilot gear pump is bad.
   • Check the pressure at the pilot filter. Refer to the Testing and Adjusting, "Pilot Oil Pressure - Check". If the pressure is less than 6800 kPa (990 psi), replace the pilot gear pump.

3. There are restrictions in the pilot lines between the filter and the pilot manifold.
   • Check the pressure at the high pressure tap on the pilot manifold. Refer to the Testing and Adjusting, "Pilot Oil Pressure - Check". If the pressure is less than 6800 kPa (990 psi), inspect the pilot lines for restrictions.

4. The swivel is damaged.
   • Plug the line to the track tension system at the swivel. Adjust the pilot relief valves. Refer to the Testing and Adjusting, "Relief Valve (Pilot) - Test and Adjust". If the pilot relief valves can be adjusted, test the swivel for damage. Refer to the Testing and Adjusting, "Swivel - Test". If the relief valves cannot be adjusted, replace both relief valves and adjust the relief valves. Refer to the Testing and Adjusting, "Relief Valve (Pilot) - Test and Adjust".

Problem: The pilot system pressure is too high.

Probable Cause

1. The pilot relief valves are set incorrectly.
   • Adjust the pilot relief valves. Refer to the Testing and Adjusting, "Relief Valve (Pilot) - Test and Adjust".

Problem: The margin pressure cannot be set on one of the implement piston pumps.

Probable Cause

1. A rod is dropped in the implement piston pump.
   • Check for a rod that is dropped in the pump. Refer to the Testing and Adjusting, "Minimum Angle Servo - Inspect".

2. The load sensing control spool in the pump regulator of the affected pump is damaged or sticking.
   • Remove the load sensing control spool from the regulator. Clean the load sensing control spool and inspect the spool for damage.

3. The implement piston pump is bad.
   • Perform the case drain test on the affected pump. Refer to the Testing and Adjusting, "Case Drain - Test".

4. The cam in the affected pump is broken.
   • Inspect the cam in the affected pump.

Problem: The margin pressure cannot be set on all of the implement piston pumps.

Probable Cause

1. The power shift pressure is incorrect.
   • Check the power shift pressure. Refer to the Testing and Adjusting, "Power Shift Pressure - Check". If the power shift pressure is not within specifications, calibrate the Caterpillar Underspeed System. Refer to the Testing and Adjusting, "Caterpillar Underspeed System - Calibrate". If the Caterpillar Underspeed System will not calibrate, refer to the "Problem: The Caterpillar Underspeed System does not calibrate".

2. The margin relief valves are damaged.
   • Remove the spools in the margin relief valves. Inspect the spools in the margin relief valves. Remove the springs. Inspect the springs.

3. An implement piston pump is bad.
   • Perform the case drain test on the implement piston pumps. Refer to the Testing and Adjusting, "Case Drain - Test".

4. The load sensing control spool in the pump regulator of the affected pumps is damaged or sticking.
   • Remove the load sensing control spools from the regulators. Clean the load sensing control spools and inspect the spools for damage.

Problem: The destroke pressure cannot be set on an implement piston pump.

Probable Cause

1. A rod is dropped in the implement piston pump.
   • Check for a rod that is dropped in the pump. Refer to the Testing and Adjusting, "Minimum Angle Servo - Inspect".

2. The horsepower control spool in the pump regulator of the affected pump is damaged or sticking.
   • Remove the horsepower control spool from the regulator. Clean the horsepower control spool and inspect the spool for damage.

3. The power shift pressure is incorrect.
   • Check the power shift pressure. Refer to the Testing and Adjusting, "Power Shift Pressure - Check". If the power shift pressure is not within specifications, calibrate the Caterpillar Underspeed System. Refer to the Testing and Adjusting, "Caterpillar Underspeed System - Calibrate". If the Caterpillar Underspeed System will not calibrate, refer to the "Problem: The Caterpillar Underspeed System does not calibrate".

Problem: The Caterpillar Underspeed System does not calibrate.

Probable Cause

1. The sensor for the Caterpillar Underspeed System is bad.
   • Check the sensor for proper operation.

2. The proportional reducing solenoid valve is bad.
   • Replace the proportional reducing solenoid valve.

3. The fuel sensor on the engine is bad.
   • Check the fuel sensor for proper operation.

Problem: The load sensing signal relief valve cannot be adjusted.

Probable Cause

1. The pilot pressure to the load sensing signal relief valve is incorrect.
   • Check the pilot pressure at the load sensing signal relief valve. Refer to the Testing and Adjusting, "Pilot Oil Pressure - Check". If the pilot oil pressure is not within specifications, proceed to Step 5. If the pressure is within specifications, proceed to the next step.

2. The load sensing signal relief valve is bad.
   • Replace the load sensing signal relief valve.

3. The line relief valves are not set correctly.
   • Check the line relief valves. Refer to the Testing and Adjusting, "Relief Valve (Line) - Test and Adjust". If the line relief valves cannot be adjusted, inspect the line relief valves for damage. If damage is found, replace the line relief valves.

4. If the machine is equipped with main relief valves, the main relief valves are bad.
   • Check the main relief valves. Refer to the Testing and Adjusting, "Relief Valve (Main) - Adjust".

5. The pressure at the low pressure tap on the pilot manifold is incorrect.
   • Check the pilot oil pressure at the low pressure tap on the pilot manifold. Refer to the Testing and Adjusting, "Pilot Oil Pressure - Check". If the pilot oil pressure is not within specifications, refer to the "Problem: The pilot system pressure is too low".

6. The ladder is not raised.
   • Check the position of the ladder in the Vital Information Management System (VIMS). Refer to the Testing and Adjusting, "Ladder Position - Check". If the VIMS does not indicate that the ladder is raised, visually inspect the position of the ladder. If the ladder is raised and the VIMS indicates that the ladder is down, the ladder position switch should be checked. Refer to the Testing and Adjusting, "Position Switch (Ladder) - Check and Adjust".

7. The travel alarm does not sound when the travel control lever is actuated.
   • If the travel alarm does not sound when the travel control lever is actuated, proceed to Step 10. If the travel alarm does sound when the travel control lever is actuated, proceed to the next step.

8. There is no pilot pressure between the pilot manifold and the ladder position solenoid valve.
   • Check the pressure between the pilot manifold and the ladder position solenoid valve. Refer to the Testing and Adjusting, "Pilot Oil Pressure - Check". If there is no pressure, replace the travel parking brake dual pressure control valve.

9. The ladder position solenoid is not receiving the correct electrical signal.
   • If the ladder position solenoid is not receiving the correct electrical signal, determine the cause and repair.

10. The hydraulic activation control lever is not in the engaged position.
    • Verify that the hydraulic activation control lever is in the correct position in order to operate the machine. Refer to the Operation and Maintenance Manual for the operating position of the hydraulic activation control lever.

11. Other implement functions do not operate.
    • Actuate another implement function. If the other implement function does not operate, replace the hydraulic activation control selector valve. If the other implement function operates, actuate the travel control lever in both directions. If the problem is not resolved, replace the travel pilot valve.

Problem: The line relief valves are noisy and are too hot to the touch.

Probable Cause

1. The main system pressure is not within specifications.
   • Check the main system pressure at the implement high pressure screens. Refer to the Testing and Adjusting, "Main System Pressure - Check". If the main system pressure is not within specifications, adjust the load sensing signal relief valve. Refer to the Testing and Adjusting, "Relief Valve (Load Sensing Signal) - Test and Adjust". If the load sensing signal relief valve cannot be set, refer to the "Problem: The load sensing signal relief valve cannot be adjusted".

2. The circuit pressure on the affected circuit is not within specifications.
   • Check the circuit pressure on the affected circuit. Refer to the Testing and Adjusting, "Circuit Pressure - Check". If the circuit pressure is not within specifications, adjust the line relief valve. Refer to the Testing and Adjusting, "Relief Valve (Line) - Test and Adjust". If the line relief valve cannot be adjusted, replace the line relief valve.

3. The line relief valve for the affected circuit is damaged.
   • Inspect the line relief valve for the affected circuit. If the line relief valve is damaged, replace the line relief valve.

Problem: The swing dual pressure relief valve cannot be adjusted.

Probable Cause

1. The pilot pressure to the swing dual pressure relief valve is not correct.
   • Check the pilot pressure to the swing dual pressure relief valve. Refer to the Testing and Adjusting, "Pilot Oil Pressure - Check". If the pilot pressure at the swing dual pressure relief valve is 4000 kPa (580 psi), replace the swing dual pressure relief valve. If the pilot pressure at the swing dual pressure relief valve is less than 4000 kPa (580 psi), proceed to the next step.

2. The pilot pressure at the low pressure tap on the pilot manifold is not correct.
   • Check the pilot pressure at the low pressure tap on the pilot manifold. Refer to the Testing and Adjusting, "Pilot Oil Pressure - Check". If the pilot pressure at the low pressure tap is not 4000 kPa (580 psi), refer to the "Problem: The pilot system pressure is too low". If the pilot pressure at the low pressure tap is 4000 kPa (580 psi), proceed to the next step.

3. A resolver valve in the resolver manifold is damaged.
   • Inspect the resolver valves in the resolver manifold. Refer to the Testing and Adjusting, "Shuttle Valves (Pilot Resolver) - Inspect". Replace any damaged resolver valves.

4. There is blockage in the line between the resolver manifold and the swing dual pressure relief valve.
   • Inspect the lines between the resolver valve and the swing dual pressure relief valve for restrictions. Remove any restrictions that are found.

Problem: Instability in the swing dual pressure relief valve

Probable Cause

1. The pilot pressure at the low pressure tap on the pilot manifold is fluctuating.
   • Check the pilot pressure at the low pressure tap on the pilot manifold. Refer to the Testing and Adjusting, "Pilot Oil Pressure - Check". If the pilot pressure at the low pressure tap is fluctuating, inspect the low pressure pilot relief valve for damage. Replace the low pressure relief valve if there is damage.

2. The high pressure cut screw on the swing pump regulators is not screwed in all the way.
   • Inspect the high pressure cut screw on the swing pump regulators. If a high pressure cut screw is not screwed in all the way, screw in the high pressure cut screw all the way.

3. A swing piston pump is bad.
   • Check the case drain on the swing piston pumps. Refer to the Testing and Adjusting, "Case Drain - Test". If a case drain test shows a swing piston pump to be bad, replace the swing piston pump.

4. The destroke pressure on the swing piston pumps is out of adjustment.
   • Set the destroke pressure on the swing piston pumps. Refer to the Testing and Adjusting, "Piston Pump (Swing) - Test and Adjust".

Problem: The hydraulic oil temperature is too high.

Probable Cause

1. The ambient temperature is too high.
   • Check the ambient temperature. Refer to the Testing and Adjusting, "Vital Information Management System (VIMS) - Check". If the ambient temperature is below 55 °C (131 °F), proceed to the next step. The machine is not designed to work in environments above 55 °C (131 °F).

2. There is a restriction of air flow through the air cooler.
   • Check for restriction of air flow through the air cooler.

3. There is aeration in the hydraulic oil.
   • Check for aeration in the hydraulic oil. Refer to the Testing and Adjusting, "Aeration in Oil - Check". If aeration is found in the hydraulic oil, refer to the "Problem: There is a large amount of air in the hydraulic oil".

4. The hydraulic cooling fan speed is not within specifications.
   • Check hydraulic cooling fan speed. Refer to the Testing and Adjusting, "Piston Pump (Hydraulic Cooling) - Test and Adjust". If the hydraulic cooling fan speed is not within specifications, adjust the fan speed.

5. The hydraulic oil cooler temperature sensor is bad.
   • Check the hydraulic oil cooler temperature sensor. If the hydraulic oil cooler temperature sensor is bad, replace the sensor.

6. There are restrictions to the oil flow through the oil cooler.
   • Check for restriction of oil flow through the oil cooler. Inspect the inlet screen for the oil cooler. Inspect the oil filters in the return lines.

7. The cooler bypass relief valve is damaged.
   • Check the cooler bypass relief valve. Refer to the Testing and Adjusting, "Relief Valve (Cooler Bypass) - Adjust".

Problem: The hydraulic oil temperature is too low.

Probable Cause

1. The ambient temperature is too low.
   • Check the ambient temperature. Refer to the Testing and Adjusting, "Vital Information Management System (VIMS) - Check". If the ambient temperature is below -20 °C (-4 °F), contact product support.

2. The hydraulic cooling fan speed is not within specifications.
   • Check hydraulic cooling fan speed. Refer to the Testing and Adjusting, "Piston Pump (Hydraulic Cooling) - Test and Adjust". If the hydraulic cooling fan speed is not within specifications, adjust the fan speed.

3. The hydraulic oil cooler temperature sensor is bad.
   • Check the hydraulic oil cooler temperature sensor. If the hydraulic oil cooler temperature sensor is bad, replace the sensor.

4. The cooler bypass relief valve is damaged.
   • Check the cooler bypass relief valve. Refer to the Testing and Adjusting, "Relief Valve (Cooler Bypass) - Adjust".

Problem: There is a large amount of air in the hydraulic oil.

Probable Cause

Note: If the machine has been repaired recently, perform the purge procedure. Refer to the Testing and Adjusting, "hydraulic System - Purge".

1. There is leakage in the suction lines.
   • Check for leakage in the suction line. Refer to the Testing and Adjusting, "Aeration in Oil - Check". Verify that the bands are diametrically opposed.

2. The breaker relief valve on the hydraulic tank is damaged.
   • Check the breaker relief valve on the hydraulic tank for proper operation. Refer to the Testing and Adjusting, "Aeration in Oil - Check".

3. There are loose baffles in the hydraulic tank.
   • Check the baffles in the hydraulic tank. Refer to the Testing and Adjusting, "Aeration in Oil - Check".

4. The head seal in one or more of the hydraulic cylinders is damaged.
   • Check the hydraulic cylinders for damaged head seals. Refer to the Testing and Adjusting, "Hydraulic Cylinder - Inspect".