Taking things one day a time — a phrase you’ve no doubt heard, and one that applies to proper excavator maintenance. Within each day, there are inspections to make, attachments to choose and, of course, an actual job to do. A true maintenance-focused ownership strategy takes all of those decisions into account each and every day because letting any of them slide affects the long-term performance of a machine.
Start with a Look
Before hopping in the machine for the day, a basic inspection should be performed. Rob Palermo, Product Manager of Excavators for Volvo Construction Equipment, says start with a broad, visual check. Is there any type of play in the controls? Does anything look off? Are there indications of leaks? Is a track pad broken or chipped? Do any areas need greased?
“Things like that need to be constantly checked over the life of the machine. If you don’t continue to keep up, it will hurt your resell value after 8,000, 10,000, 12,000 hours,” says Palermo.
Then, move up close. Check all of the fluid levels — engine oil, coolant surge tank, fuel and, now with Tier 4 Final machines, diesel exhaust fluid (DEF).
“Making sure DEF is topped off is an important new step now,” says Matt Hendry, Excavator Product Consultant for John Deere. “What we say is when you fill up the fuel, top off the DEF — it’s 1 to 1, basically. That’s how we’re trying to drive the consistency for checking it.”
Philippe Bisson, Brand Marketing Manager for Case Construction Equipment, notes that those fluid checks are more than just prep work for the day ahead. Fuel levels can leave clues for uncovering broader equipment issues.
“Did the excavator suddenly use 40 percent more fuel today than it usually does? That could indicate that the engine was compensating for some other weakness in the machine,” says Bisson. “Checking these factors with an analytical eye can help keep equipment running in peak condition.”
Walk to the pump side of the machine and visually inspect all of the filters — engine oil, external hydraulic, pilot and fuel filters. Hendry emphasizes the importance of checking those fuel filters and the water separation bowl — draining out the bowls on a daily basis is “critical.” If too much water is allowed to accumulate, it may get into the fuel, which could possibly degrade the engine by 80 percent and shift it into protect mode.
“That’s the one that can really reach up and sting you hard if you don’t maintain that,” he says. “We get a lot of calls about that one — operators just ignoring the fuel filters and letting water build up in the system. The common rail pressures on the engine are very high today, and you’re trying to keep water out of that common rail. The sensors are sensitive as to how much water they’ll allow in the fuel.”
On Deere excavators, specifically, Hendry also recommends draining any excess water that’s made its way into the system from the bottom of the fuel tank weekly (or monthly at a minimum) via the stainless steel sump in the bottom of the fuel tank.
Assess the Attachments
Attachments need the same level of inspection as the excavator, to spot potential maintenance issues as well as other inefficiencies.
For example, with ground-engaging tools, check the bucket and its teeth. A worn tooth will affect the area around it, the long-term health of the bucket and its digging performance. But consider what else those wear patterns or issues might mean.
“If two operators in an organization are operating similar machines in similar applications and are experiencing differing wear patterns, why is that? Operator inefficiency? Issues with the machine?” says Bisson. “Differing wear patterns on similar machines provide that proof to look further into it.”
Attachment selection is another daily decision that affects the long-term viability of an excavator. Too small of a bucket will be inefficient; too large a bucket will place too much stress on the machine. Mismatching a hammer to a machine’s auxiliary hydraulics will create inefficiency either on the part of the machine or the attachment. And so on.
But even with the perfect attachment selection for the job, there are maintenance ramifications, considering both the job and the tool used.
“Heavy attachment use, such as hammers and plate compactors, puts greater stress on the hydraulic systems and on the excavator’s boom and arm,” says Bisson. “And it’s a physically rough application with a lot of vibration and force. Take extra time to check the structural integrity of the boom, the arm, hydraulic connections and fittings and hydraulic fluid levels.
Consider an excavator that is mostly running a hammer attachment. A big hammer produces a ton of impact that sends energy back to the machine. This additional stress on the machine will require additional attention during the daily inspection. The bolts that go through the pin connecting the arm to the boom are critical components to monitor because they will loosen from the vibration.
“I’ve seen pins lock out on those when they are not paying attention,” says Hendry. “You have to add a really rigorous daily inspection when using a high vibration, high impact attachment like a hammer or a rotary rock cutter.”
Palermo also notes that if you are constantly running a hammer on a particular excavator, there is an option for an additional return filter just to protect the hydraulic system, which adds another maintenance item to the list.
Operation Plays its Part
All of these little maintenance checks and balances keep the excavator operating as it should, but then comes the even harder part — operating it as it should be operated.
At the most basic level, the lifetime of a machine is determined by how much fuel is going through it. So, operating a machine in a way that uses more fuel than necessary will wear it out ahead of schedule.
Palermo says that many machines today are capable of operating a job at a lower rpm while achieving the same level of productivity as the higher level.
“Operators need to learn that they don’t need to go all the way up to max H mode all the time for every application,” says Palermo. “We try to teach that. Drop into a lower mode and see if your productivity stays the same. It will save the machine, fuel and is the way around a lower cost per ton.”
On the other hand, excessive idling is also a big issue. Bisson still sees idling that exceeds 40 to 50 percent in some applications, which, again, is additional engine wear and additional engine hours.
“Those hours go against the lease,” he says. “Those hours go against the warranty and ultimately shorten the window on when certain repairs and components are covered by the OEM. Curbing engine idling can significantly lower total owning and operating costs. Many OEMs offer auto shut-off functionality to prevent excessive idling.”
“On a hydraulic excavator, your hydraulic pumps are on-demand, so one works all the time and the second pump opens up as needed so as to not constantly move,” says Hendry. “Some attachments have such requirements that you have to fool the second pump to work all the time. So, now you are moving the entire volume constantly, which can create an oil heating issue, but you’re also at full demand on the pumps, so there is a higher demand on the engine for fuel, and so on.”
Also, be sure to watch the hydraulic temperature during the day because of the intense oil demand.
Finishing Up the Day
The job is finished, but your holistic maintenance routine isn’t done. Before walking away from the machine for the day, look at the undercarriage and clean out any dirt, rocks and debris. According to Bisson, up to 40 percent of an excavator’s lifecycle costs come from the undercarriage.
“Dirt and rock contributes heavily to wear and can be removed in a few minutes,” says Bisson. “In winter, accumulated material freezes and expands and can cause damage and operational problems. Cleaning will also reveal worn bushings or other undercarriage components in need of repair, instead of concealing them.”
Undercarriage wear/damage kicks off a domino effect: One worn component puts undue stress on the next component and so on, which will cause greater wear and damage.
Look for accumulation of any fluid on the machine or on the ground surrounding it both before and after operation in order to catch any leaks as early as possible. Catching such a problem at the end of the day, if possible, instead of in the morning, gives your service team more repair time and hopefully avoids a more prolonged period of lost productivity.
Also be sure to fill up the tank before putting the machine away. This isn’t just a courtesy for the next day because moisture will form in the space between the top of the tank and the fuel as the atmosphere in the tank cools. The bigger that gap, the more water that will generate over time inside the fuel tank.
Making all of these steps a part of your daily routine — before, during and after operation — will give any excavator the best chance to perform at its peak for the longest period of time.
Chris Crowell is a Contributing Editor of Utility Contractor.