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The Cost of Engine Idling: How Letting Your Equipment Idle Can Worsen Your Fleet

The Cost of Engine Idling: How Letting Your Equipment Idle Can Worsen Your Fleet

Man standing by his machine as it idles

The Cost of Engine Idling: How Letting Your Equipment Idle Can Worsen Your Fleet

Reading time: 5 min

While heavy equipment is designed to handle rigorous environments and challenging workloads, much of a machine’s time on the job is spent idling. In fact, it is estimated that around 40% of a machine’s operating hours are spent idling.

 Frequently, machines sit idle while operators switch between tasks. Another common scenario in which machines are left idle is when operators are working in tandem with other machines and operators. For example, an excavator working with a dump truck may sit idle while the dump truck drives across the job site to dump excavated topsoil.

Although idling may seem benign, it has the potential to cause serious damage to your heavy equipment and reduce the efficiency of your fleet.

In this guide, we’ll delve into the dangers of allowing heavy equipment to idle for too long. Then, we’ll go over tips and strategies to help mitigate the impact of idling on your heavy equipment. Learning these strategies will help you extend the longevity of your heavy equipment and improve your team’s efficiency on the job.

The Impacts of Engine Idling

When your machine idles, the engine still needs to burn fuel to continue running. Since it is not performing any work, however, idling is an inefficient use of fuel and contributes to engine wear without any benefit. Here are the main impacts of letting your machine’s engine idle.

Impacts to Your Heavy Equipment

The most detrimental effects of allowing your machine to idle are related to the machine’s engine and its components. There are a number of conditions that can occur when the engine is left to idle excessively.

Wet Stacking

Wet stacking can occur when a diesel engine becomes too cool and the fuel in the engine’s cylinders isn’t fully combusted. The excess, uncombusted fuel eventually builds up, or stacks, in the machine’s exhaust system.

When the machine begins operating normally and the engine heats back up, this fuel may burn off in the exhaust, resulting in the emission of a dark fluid and plumes of black smoke. Excess idling may create the conditions for wet stacking to occur, since idling for too long can cause the engine’s temperatures to drop.

Cylinder Washing

If left idling for too long, a machine’s engine may become too cool. When this occurs, fuel in the engine’s cylinders isn’t fully combusted and excess fuel may run down the inside walls of the cylinders.

This process, called cylinder washing, may strip the oil from inside the cylinders, thereby making the engine more susceptible to damage. Over time, the uncombusted fuel will contaminate the oil, requiring more frequent oil changes and causing additional wear to engine components.

Excess Wear

When idling, a machine’s engine is still running. The engine’s cylinders, pistons, belts and other key wear components still have to perform their functions.

Therefore, idling still wears down your machine’s engine, even though no work is being performed. Over time, this excess wear will cause your engine to require additional maintenance, more frequent oil changes and could even lead to premature component failures.

Increased Operating Costs of Engine Idling

Perhaps the most alarming impact of excess idling comes in the form of increased operating costs. Just because your engine is idling, this does not mean fuel isn’t being consumed.

In fact, a single hour of idling consumes as much diesel fuel as driving your machine 25 miles. Fuel represents a major operating cost for any fleet, so consuming so much fuel without any benefit is wildly inefficient.

In addition to increased operating costs from unnecessary fuel consumption, excess idling can cause other operating costs to balloon, as well. Excess idling may require DEF, oil, bearings and oil filters to be changed more frequently, inflating your operating costs further.

Environmental Impacts of Engine Idling

Not only is idling bad for your machine and budget, it’s bad for the environment too. Idling machines emit a host of toxic pollutants such as sulfur dioxide, particulate matter, carbon monoxide, carbon dioxide and nitrogen oxides. These pollutants degrade air quality, posing a health risk to your team and your project’s surroundings.

Idling machines don’t just contaminate the air, they also generate noise, which can be unnecessarily disruptive to nearby businesses and residential areas.

By minimizing excess idling, you can keep these environmental disturbances to a minimum, thereby minimizing your impact to the environment and fostering a better work environment for your team.

How to Minimize Excess Idling

While some idling is unavoidable, there are some strategies you can put in place to try and minimize excess idling. Here are some areas to address:

  • Improve your project’s workflow so that machines don’t sit idle waiting for other tasks to be completed.
  • Use a telematics system like EquipmentShare’s T3 to monitor your fleet’s idle time, paying particular attention to operators who have higher-than-average idle time.
  • Use high quality lubricants that will reduce the impact of idling on your engine’s performance and minimize excess wear.
  • Equip your machines with auto-idlers, or idle limiters, that can adjust engine speed or turn off the engine once a machine has been idling over a certain amount of time.
  • Train operators about the importance of reducing idling time and its impact on fuel consumption, emissions and equipment wear and tear.
  • Strategically position equipment to minimize the need for long travel distances, which can lead to extended idling periods.

By implementing the strategies above, you can make a significant improvement to the amount of time your fleet spends idling on the job, leading to financial savings, reduced emissions and improved equipment efficiency.

Final thoughts

Reducing your fleet’s idle time is the key to improving the efficiency of your heavy equipment fleet, increasing longevity, lowering operating costs and reducing your impact on the environment. Some strategies to reduce your fleet’s idle time include tapping into telematics systems, implementing auto-idlers, providing adequate training to operators and improving project organization and workflow.

While it isn’t possible to eliminate all idle time, implementing these strategies is the best way to make a significant improvement in the amount of time your heavy equipment spends idling on the job.

Experiencing machine wear due to excess idling? Check out the EquipmentShare Shop’s extensive online parts catalog to find the right components for your equipment. Our growing catalog features OEM and aftermarket parts from some of the industry’s leading manufacturers. Can’t find the part you need? Reach out to our parts experts and get personalized assistance.

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