Volvo SD115 Regen Issues: Diagnosis and Solutions

[MikePhua]

The Volvo SD115 is a robust, highly versatile tandem drum roller designed for various compaction tasks on construction sites, highways, and infrastructure projects. Like any modern machinery, it integrates advanced engine technology, including a diesel particulate filter (DPF) system that requires periodic regeneration. However, issues with regeneration processes can arise, causing performance issues and downtime. This article will address common regeneration (regen) problems with the Volvo SD115, exploring potential causes, troubleshooting methods, and solutions.
What is Regeneration in Heavy Equipment?
Regeneration is the process by which a diesel engine’s exhaust system burns off soot particles accumulated in the diesel particulate filter (DPF). The DPF is designed to trap these particles to meet emissions standards, but over time, the accumulated soot needs to be cleared to maintain engine performance and compliance with emissions regulations.
Regeneration occurs in two forms:

• Passive Regeneration: This happens automatically when the exhaust temperature is high enough, such as during normal operation, particularly at highway speeds or under load.
  
• Active Regeneration: If passive regeneration doesn’t occur enough, the system will trigger active regeneration, where extra fuel is injected into the exhaust to increase the temperature and burn off the soot.
  

Common Volvo SD115 Regen Issues
When a Volvo SD115 faces regen issues, it can result in various symptoms such as reduced engine performance, increased fuel consumption, or even engine shutdowns. Understanding the most common causes of these issues is key to resolving them.

1. Frequent Active Regen Cycles
   One of the most common problems is when the Volvo SD115 performs frequent active regeneration cycles. This can happen if the DPF is not able to burn off soot particles effectively during passive regeneration, forcing the engine to go into active regeneration too often.
   Causes:
   • Short trips or idle time that do not allow for sufficient exhaust temperatures to burn off soot.
     
   • Clogged or partially blocked DPF, which restricts the flow of exhaust gases.
     
   • Low-quality diesel fuel, which may result in higher soot production.
     
   Symptoms:
   • Engine performance issues.
     
   • Increased fuel consumption.
     
   • The regeneration process frequently being triggered.
     
2. Incomplete Regeneration
   Another problem is when the regeneration process begins but does not complete, often due to the DPF not reaching the required temperature to fully clear the soot. Incomplete regeneration can lead to soot buildup over time, which may eventually result in a blocked filter.
   Causes:
   • Faulty or malfunctioning temperature sensors that do not properly monitor the exhaust temperature.
     
   • A malfunctioning fuel injector or the fuel delivery system that prevents the proper amount of fuel from being injected to facilitate the regeneration process.
     
   • An insufficiently heated exhaust system, especially in machines used in colder climates.
     
   Symptoms:
   • Warning lights on the dashboard indicating a regeneration issue.
     
   • Reduced engine power.
     
   • Abnormal engine noises during or after regeneration cycles.
     
3. DPF Clogging or Blockage
   If the DPF becomes excessively clogged, it may cause frequent regeneration attempts that are unsuccessful. This problem typically occurs when soot buildup is not adequately managed or when the regeneration cycles are incomplete, causing a severe reduction in the efficiency of the exhaust filtration system.
   Causes:
   • Excessive idling or low-load operation where regeneration isn’t triggered frequently enough.
     
   • Extended operation with incorrect or poor-quality fuel.
     
   • Insufficient or interrupted regeneration cycles.
     
   Symptoms:
   • The machine may enter into a “limp” mode where engine power is reduced to prevent further damage.
     
   • Persistent warning lights related to the DPF or exhaust system.
     
   • Noticeable engine hesitation or misfire during operation.
     
4. Sensor Malfunctions
   The regeneration system relies on multiple sensors to monitor conditions like exhaust temperature, pressure before and after the DPF, and fuel injection. When any of these sensors fail or provide incorrect readings, the regeneration process may not function as intended, leading to various operational issues.
   Causes:
   • Faulty exhaust temperature or pressure sensors.
     
   • Dirty or malfunctioning EGR (Exhaust Gas Recirculation) valve, which can affect the exhaust flow.
     
   • Corroded or damaged wiring and connections to the sensors.
     
   Symptoms:
   • Warning lights or error codes on the display panel.
     
   • The engine does not perform regenerations when it should.
     
   • An increase in exhaust temperatures or engine performance drops.
     
5. Excessive Fuel Consumption
   Another side effect of issues with regeneration is an increase in fuel consumption. When the DPF is clogged or regeneration is happening too often, the engine consumes more fuel to maintain the necessary temperature for the process. This can be a significant operational cost, particularly for equipment used in high-demand environments.
   Causes:
   • Continuous or incomplete regeneration cycles.
     
   • Poor fuel quality or incorrect fuel mix.
     
   • A faulty fuel delivery system or fuel injectors.
     
   Symptoms:
   • A noticeable increase in fuel usage compared to normal operation.
     
   • Frequent need for refueling despite not using the machine for prolonged hours.
     

Diagnosing and Troubleshooting Volvo SD115 Regen Issues
If your Volvo SD115 is experiencing regen problems, the following steps can help diagnose the issue:

1. Check for Error Codes and Warning Lights
   The Volvo SD115 is equipped with diagnostic systems that can provide error codes related to the regeneration system. Using a diagnostic tool, you can read these codes to pinpoint the specific issue, such as a faulty sensor or DPF blockage.
   
2. Inspect the DPF
   If the regeneration process is not completing, or the system is frequently attempting active regeneration, it’s important to inspect the DPF for any signs of clogging. Cleaning or replacing the filter may be necessary if the filter is severely blocked.
   
3. Check Fuel Quality
   Make sure that high-quality diesel fuel is being used in the Volvo SD115. Contaminated or poor-quality fuel can cause excessive soot buildup, which hampers the DPF’s ability to regenerate efficiently.
   
4. Inspect Sensors and Connections
   Sensors that monitor exhaust temperature, pressure, and the EGR system should be inspected for malfunctions or dirt buildup. Faulty sensors should be replaced, while dirty sensors can usually be cleaned.
   
5. Monitor Regeneration Cycles
   It’s important to allow enough time for the regeneration process to complete. If the machine is used only for short trips or low-load operations, you might need to perform a manual forced regeneration to clear the soot.
   

Solutions and Preventive Measures

1. Manual Regeneration
   If automatic regeneration cycles are not completing, you may need to initiate a manual regeneration process. Refer to the operator’s manual for the procedure, which usually requires the machine to be idling for a set period of time in a safe location.
   
2. DPF Replacement or Cleaning
   For severely clogged filters, cleaning or replacing the DPF may be necessary. Some machines allow for the DPF to be cleaned using special machines, while others require full replacement. Regular cleaning can extend the lifespan of the DPF and prevent costly repairs.
   
3. Regular Maintenance and Monitoring
   Keep an eye on the machine’s regen process by following a regular maintenance schedule. Ensuring the fuel system is clean, sensors are functioning correctly, and the exhaust system is clear of blockages will help maintain the efficiency of the regeneration system.
   
4. Optimal Machine Operation
   To avoid regeneration issues, try to operate the Volvo SD115 in conditions that allow for passive regeneration. Longer trips with higher load demands allow the system to burn off soot naturally without triggering frequent active regeneration cycles.
   

Conclusion
Regeneration issues with the Volvo SD115 can cause performance problems and operational inefficiencies, leading to higher maintenance costs. By understanding the common causes and performing thorough troubleshooting, operators can identify the root cause of the issue and take appropriate action. Regular maintenance, proper fuel quality, and ensuring the regeneration system functions smoothly can significantly improve the lifespan and performance of your Volvo SD115 roller, ensuring it continues to deliver reliable performance on your job sites.