Idle time is a significant, but often unrecognised problem for fleet operators. The following article by Steve Croxon was published in Griffith City Council’s internal newsletter Council Capers, but FLEET intouch think it deserves a bigger audience.

The lessons apply to everyone operating a plant and vehicle fleet and is a terrific example of how awareness can be raised around the issue of plant and vehicle idle time.

Excessive engine idling

Diesel engines play an important part in today’s transport, farming and constructions industries. They are a durable and economical source of power. There is, however, a growing concern about the health effects of exposure to diesel exhaust, particularly for asthmatics and others with lung and other respiratory problems. Fortunately, new emission standards and new technology are helping to ensure that the cleaner diesel engines of the future will dramatically reduce these health risks.

There are several things now that are available to us to save money and reduce pollution. A lot of idling practices came about due to earlier diesel engines being difficult to start so once the engine was started it was not switched off until the end of the day’s work (E.g. Lance Bulldog, Field Marshall etc.). Most modern diesel engines start easily with very little problems. There has been concern with turbo cool down periods in the past which have been overcome by later model turbo chargers, which are liquid cooled and have longer lasting bearings. Therefore, idling of engines for any more than a couple of minutes at start up or shut down is not needed, wastes fuel and adds costs to the works.

Idling wastes fuel and money

A typical truck burns approximately 3.5 litres of diesel per hour idling. If a truck idles 25 percent of its working life and works 8 hours per day over 48 weeks per year this equates to 1680 litres of fuel consumed idling at a cost of approximately $2,436 per year. Idling causes excessive engine wear Running an engine at low speed (idling) causes twice the wear on internal parts compared to operating at regular speeds. According to the American Trucking Association, such wear can increase maintenance costs by almost $2,000 per year and shorten the life of the engine.

Unnecessary idling causes pollution

Idling vehicles can emit significant amounts of pollution, including carbon dioxide, which contributes to global climate change; nitrogen oxides and volatile organic compounds, both of which contribute to the formation of ozone smog; poisonous carbon monoxide; and particulate matter.

Increased service intervals

In the example above of 25% idle time, would mean that there will be more services and downtime over the life of the vehicle. Should the life of the vehicle be estimated at 10,000 hours and the unit is serviced every 250 hours, 10 extra services would be required at a total cost of around $4,500

Loss of capital value

Generally, when trading or selling an item of plant the prospective purchaser values the equipment taking the hour-meter (hours worked) into consideration. If a machine has spent time idling this is unproductive time that has accrued on the hour meter which devalues the machine when it is disposed. An example would be a Caterpillar 12H grader one with 10,000 hours on the hour meter and the other with 7500 hours on the hour meter. The excess hours devalue the machine by approximately $30,000.

So all up excessive idling can cost a significant amount of money and in turn make a fleet of vehicles and plant unnecessarily expensive to run.

Tips to reduce idling

• Vehicles should never be left idling whilst unattended
• Engine warm-up periods should not exceed 2 minutes (provided that required air brake pressure and other critical settings have been reached)
• Vehicles should be shut off if idling time is expected to exceed two minutes, unless the health and safety of employees is or may be jeopardised or the unit is required to be running to power auxiliary equipment. (Work Platforms Cranes etc.).