Veteran loggers may remember a time when they could simply fill up their forestry equipment with diesel and get to work without much thought. However, there’s a lot more to think about now with more sophisticated engines, newer ultra-low-sulfur diesel (ULSD) and more stringent environmental regulations.

The hot, humid weather that comes with southern summers presents its own set of maintenance challenges when it comes to fuel, especially this year, with the new EPA-mandated fuel requirement. Here are a few reminders to help keep your equipment—and your business—running smoothly, no matter how high the temperature or the humidity rises.

Humidity and water—It’s easy for summertime humidity to create engine-damaging water in your fuel, but you can take these steps to minimize problems that excess moisture can cause. Start with your on-site fuel tanks, especially if you use both a central storage tank and smaller, portable tanks to deliver fuel to machines.

Every time you manipulate your fuel—transferring it from the delivery truck to the storage tank to the portable tank, for example—there is a chance of contaminating your fuel with dirt and/or water. Water contamination happens more often on cool nights when the dew point is lower as the humid air in the upper part of the tank contacts the cold inside walls, condensing the water and making it flow to the bottom of the tank. That moisture can cause rust to form, which in turn can be pumped into your machines with the fuel, putting unnecessary stress on fuel filters and vital components such as injectors and injector pumps. All tanks should be equipped with both water and particulate filters to minimize these potential problems.

You can protect against moisture in each machine’s fuel tank, too, with a water-dispersant additive such as John Deere’s Summer Fuel Protect, or your machine manufacturer’s specific water-dispersant additive. Check with your local dealer to determine which product you can use for this purpose. Using an additive with every fill-up may be necessary in swampy work sites or rainy conditions.

ULSD, Carbon Deposits—This summer also brings one more fuel issue with it. The EPA now requires the use of ULSD fuel for all off-road diesel engines. That’s good for the environment but it presents new maintenance challenges for you because using ULSD can lead to carbon deposits on fuel injectors. Replacing an engine’s injectors can be costly, especially since the injectors on newer motors operate at pressures 10 times higher than those on older models. Based on this, you’ll want to prevent carbon buildup in injectors by using solvent additives like John Deere’s Fuel Protect Keep Clean or your manufacturer-specified product. Adding a solvent product to each machine’s fuel system monthly can go a long way toward ensuring efficient performance and long equipment life.

Work with your fuel supplier to be sure you have the right fuel, the right additives and the right filters for all your equipment, and you’ll be better prepared to keep your operation up and running all summer long.