EGR System Maintenance: Preventing carbon buildup in heavy-duty engines

First, the EGR cooler reintroduces exhaust gases into the intake stream and uses coolant to lower their temperature. Next, the EGR valve limits how much exhaust can go back into the intake tract by receiving commands from the vehicle’s computer to open and close. However, carbon buildup occurs when soot-containing exhaust mixes with oil vapor at the origin point and can contaminate many parts of the engine. 

A thick, black buildup eventually forms on the EGR valve, and you should remove it to avoid problems with your engine and vehicle performance. Some individuals reduce carbon formation with detergents that prevent buildup on critical components and prolong operations before decarbonization becomes necessary.

Choose how to fix carbon buildup in engine components

Once carbon buildup has become problematic for diesel engines, cleaning EGR valve components and the whole system can happen in several ways. One of the most straightforward ways is to use mechanical methods that scrape the deposits off the piston tops, combustion chamber, and other affected parts. However, opening the cylinder head can be complicated, especially for people working on modern engines. 

That has led some individuals to use chemical removal methods. Some companies use special machines that deliver the products directly to the impacted engine parts to break down the accumulation. 

Additionally, a less common but emerging method is to use hydrogen decarbonization, which works for any vehicle with an internal combustion engine. This option does not require previous disassembly and removes carbon in about an hour without damaging components.

Understanding the available options is a proactive way to prevent buildup because you can plan to remove it at recommended intervals based on manufacturers’ suggestions, driving conditions, or other factors.

Recognize carbon buildup in engine symptoms

Prevention also involves understanding the indicators of trouble. Carbon accumulation in diesel engines happens gradually, so you may overlook the earliest signs of this problem. However, if not addressed, it can severely impact your vehicle’s performance and cause engine damage.

One symptom you may notice is that the engine runs roughly or seems balky for a few minutes after startup before performing normally. Fuel efficiency may also decrease while emissions increase. At the most severe levels, the buildup may cause easily detectable issues during operation, such as surging or rough idling. 

You should have comprehensive maintenance programs that determine whether built-up carbon has caused unusual engine symptoms or if there is another culprit. For example, a diesel engine’s glow plugs last up to 100,000 miles and don’t need replacing before then unless problems develop. However, excessive exhaust and rough starts can indicate it’s time to change them, showing how overlap exists between the need for decarbonization and other issues requiring attention.

Developing a system for drivers to quickly and easily submit reports about engine or performance changes is an excellent way to find and tackle carbon buildup before it gets worse.

Pursue processes to support diesel EGR system performance

Reducing the need to decarbonize diesel engines also requires making internal changes at various organizational levels. The buildup may happen more slowly on vehicles primarily used for long stretches of highway driving rather than numerous short trips separated by excessive idling. 

However, some fleet managers have recognized that cutting out idle time also benefits entire organizations. Such was the case at UPS, where executives calculated $257 million in savings by shaving 10 minutes from its delivery and departure efficiency. Coaching drivers to recognize the causes of unnecessary idling and reducing it when feasible could benefit the functionality of a diesel EGR system, too. 

Another possibility is to improve maintenance strategies so technicians check for and address deposits before they get too thick. Transitioning to a cloud-based system that automatically prompts examining parts for buildup is one option that eliminates paper-based recordkeeping or other inefficient, error-prone methods. Then, all parties handling a vehicle’s upkeep have access to the same information, even if they work from various locations.

Alternatively, some fleet managers have adopted solutions with predictive algorithms that detect abnormalities before they become noticeable. These, along with improved scheduling systems, can allow people to address carbon buildup before it impacts engine performance.

Remain proactive against carbon buildup

Although you cannot eliminate the need to decarbonize engine parts to remove deposits, these tips will keep it manageable, significantly reducing the likelihood of experiencing complications. Apply them across your organization and reinforce the idea that all parties interacting with heavy-duty vehicles contribute to their performance.