Regeneration failure with Frequent regeneration request

Today I want to talk about frequent regeneration problem of your machine. If your machine shows ‘Regeneration needed’ even though you did that within 20~30hrs repeatedly, what is the root cause and what can we do to shot this trouble? Let`s go into this. 

Symptoms

When an excavator experiences a regeneration problem, it may exhibit several responses or symptoms. Here are some possible responses when there is a regeneration issue:

1. Frequent Regen` message : It will show ‘Do parked Regeneration’ on your onboard computer repeatedly.
2. Warning lights or error codes: Modern excavators are equipped with onboard diagnostic systems that monitor various components, including the regeneration system. If a regeneration problem is detected, the excavator’s onboard computer may trigger warning lights on the instrument panel or display specific error codes related to the regeneration system.
3. Reduced engine power : When the regeneration system is not functioning correctly, the excavator’s engine may enter a reduced power or limited performance mode. This is a protective measure implemented by the engine management system to prevent damage caused by excessive soot buildup in the diesel particulate filter (DPF).
4. Abnormal rpm oscillation : When have this kind of issue, RPM of the engine can be oscillated when operating.
5. Increased fuel consumption: A regeneration problem can lead to increased fuel consumption as the engine may struggle to burn off accumulated soot in the DPF. This inefficiency can result in decreased fuel economy and higher operating costs.
6. Continuous or frequent DPF cleaning message: The excavator’s regeneration system is responsible for periodically burning off the trapped soot particles in the DPF. When the regeneration system malfunctions, the excavator may enter frequent or continuous regeneration cycles, attempting to clean the DPF without success.
7. Exhaust smoke or unusual odor: If the regeneration process fails, the excavator’s exhaust system may emit excessive smoke or produce an unusual odor due to incomplete combustion of diesel fuel or the presence of unburned particles.

Most Possible root cause and suggested solution

1. Exhaust pressure sensing related parts failure

Mainly the system diagnose its soot level by the Pressure difference between the inlet of DPF and Outlet. So if one of those related sensor out, system will diagnose that and trigger the error code or regeneration message. So recommend to check and replace the Exhaust pressure related sensor kind of parts. 

2. Exhaust system line clogged by crystallization.

When the crystallization occur inner side of the Hose or Pipe for Exhaust line, this make resistance and diagnostic system can be judge this as DPF was clogged by soot. So call the service engineer and need to check the related parts and remove the crystal if that was found.

 

1

Crystallization in Exhaust system

 

The other causes to be referred

There can be several other possible causes for regeneration problems in an excavator. Here are some common ones:

1. Soot buildup in the diesel particulate filter (DPF): The DPF is designed to trap and store soot particles from the engine exhaust. Over time, the DPF can become clogged with excessive soot buildup, reducing its ability to regenerate properly. This can happen due to extended periods of low engine load, short operating cycles, or the use of improper fuel.
2. Faulty or malfunctioning regeneration system components: The regeneration system consists of various components such as sensors, valves, injectors, and control modules that work together to initiate and control the regeneration process. If any of these components are faulty or malfunctioning, it can prevent proper regeneration from occurring.
3. Fuel quality or contamination: Poor fuel quality, such as using low-quality diesel or fuel contaminated with water or impurities, can affect the combustion process and lead to incomplete regeneration. Contaminants in the fuel can also cause damage to the regeneration system components.
4. Engine or exhaust system issues: Problems with the engine, such as faulty injectors, malfunctioning turbocharger, or exhaust leaks, can impact the combustion process and hinder successful regeneration. Issues with the exhaust system, such as a blocked or damaged exhaust pipe or muffler, can also restrict the flow of exhaust gases and impede regeneration.
5. Incorrect operating practices: Improper operating practices, such as consistently operating the excavator at low engine speeds or idling for extended periods, can contribute to regeneration problems. These practices may not generate enough heat in the exhaust system to initiate regeneration or can lead to excessive soot accumulation.
6. Sensor or software malfunctions: The regeneration system relies on various sensors to monitor exhaust temperature, pressure differentials, and other parameters to initiate and control regeneration. If any of these sensors malfunction or if there are software glitches in the control system, it can disrupt the regeneration process.
7. Maintenance neglect: Inadequate maintenance practices, such as failing to perform regular DPF cleaning or ignoring warning signs, can contribute to regeneration problems. Neglecting routine maintenance tasks can lead to accelerated soot buildup, component wear, or other issues that hinder proper regeneration.

It’s important to note that these responses may vary depending on the specific excavator model and the nature of the regeneration problem. When encountering such issues, it is recommended to consult the excavator’s operator manual, contact the manufacturer’s customer support, or seek assistance from a qualified technician to diagnose and resolve the problem properly.