Apache Sprayers now operate Tier 4 Final Cummins diesel engines, making them perform better while running cleaner and with a much smaller impact on the environment.
But, those engines do bring with them a new maintenance issue for operators. Though it’s one with which many will likely already be familiar, it’s important to ensure diesel exhaust fluid (DEF) – a key component of the engine system – is handled and stored correctly.
The Tier 4 engines that were incorporated into all 30-series Apache Sprayers in 2016 utilize DEF to help reduce emissions. The fluid – a mixture of water and urea – is applied to diesel exhaust immediately before expulsion from the engine to cut particulate matter and Nitrogen Oxides, resulting in a much more environmentally friendly, cleaner-burning machine. Tier 4 requirements, the culmination of a multi-step phasing-in of new regulations dating back to the early 2000s, were rolled out by the U.S. Environmental protection Agency (EPA) in 2011 as a way to cut diesel emissions. Machinery manufacturers have worked toward integrating the “advanced exhaust aftertreatment” technology into their engines over the last six years, and Apache Sprayers began adjusting engine emissions and working toward Tier 4 in 2012.
Tier 4 systems require a small DEF tank alongside the fuel tank. On a machine with a 90-gallon fuel capacity, the DEF tank is typically around five gallons. Although the fluid is a relatively simple combination of ingredients, it’s still important to handle and store it correctly. Failing to do so can damage the fluid, the engines in which it’s used and surrounding surfaces and components, according to Chris Smith, Apache Sprayers Application Specialist.
Follow these tips to ensure your DEF functions as required and preserves the life and longevity of your Apache Sprayer’s Tier 4 engine.
Keep things clean.
Because it is slightly corrosive, it’s important to clean up spills immediately and ensure any surface is free of DEF to avoid slow, long-term damage. “It can be hard on paint, so if you’re pouring it into your machine, you want to make sure you wipe off any excess to avoid discoloration or prevent it from eating the paint,” Smith says.
Adjust to Mother Nature.
Though it may be easy to throw a jug of DEF in the back of the pickup and keep it there until it’s time for a fill-up, that can erode the fluid’s quality. Direct sunlight can cause evaporation which can lead to imbalanced ingredients (DEF is 67.5% water and 32.5% urea) and as a result, lower efficacy. In addition to avoiding direct sunlight, it’s best to store DEF around 75 to 80 degrees Fahrenheit. Though temporary exposure to higher temperatures is okay, longer-term exposure can cause ingredient imbalance.
You don’t need to be as concerned with lower temperatures. Even if the DEF freezes, once it thaws, it is still usable. “Freezing doesn’t alter the ingredient percentages like heat does,” Smith says. “Evaporation changes the DEF completely when you lose water. But, when it freezes, the percentages stay the same and they thaw at the same time.”
Avoid cross-contamination.
Any additional chemical that’s present in your DEF can cause it to lose efficacy and can potentially damage engine components by introducing particulates or other liquids. To prevent this, use containers that aren’t used for other fluids, like engine oil or coolant. That includes large storage tanks and pumps, Smith says.
“Apache Sprayers have quality sensors in our DEF tanks, so if contaminants are picked up, it will trigger an error code and you have to drain the tank and put in clean DEF. It’s the machine’s way of making sure you’re using clean DEF,” he adds. “The best way to avoid that kind of contamination is to handle it separately – with separate containers – from other engine fluids.”
Store reasonable amounts.
The best way to ensure your DEF is not contaminated or damaged by environmental conditions is by keeping a reasonable amount on supply. Depending the amount of machinery you have requiring the fluid and how long that machinery is operated in the field each growing season, you may not need a huge supply on your farm. Some farmers keep as little as a few gallons on hand, while others use 400- or 500-gallon tanks. Working through the stock you have on hand in a timely manner is the best way to make sure your DEF isn’t beyond its normal shelf life.
“A lot depends on the operator and how much fuel he or she consumes in a given year,” Smith says. “More operators are installing larger tanks, but many still use 55-gallon drums. Matching your storage to consumption will ensure your DEF stays in good shape.”
Don’t let machinery tanks get too low.
Because of the combination of ingredients, when a tank runs low on DEF, it can trigger a quality sensor error code. When a tank is low and the fluid sloshes a lot, it can become cloudy and that physical change can be construed as a quality issue by the tank sensors. By keeping DEF levels from getting too low in on-board tanks, you can avoid this issue. “Fill it up and the issue will go away,” Smith says.
In general, since Tier 4 engines have been around for a few years, many farmers and operators will likely have some familiarity with DEF. Smith says it’s important to remember not just the best practices for storing and handling the fluid, but the necessary safety precautions.
“It’s recommended that when handling DEF, you should wear goggle and gloves just like with any agricultural chemical,” he says.
See more about Apache Sprayers’ Tier 4 engines and their benefits to performance and fuel efficiency.
