Operator technique determines the life expectancy and operating costs of most compact track loader undercarriage components.
The undercarriage can represent nearly 20% of the purchase price of a loader.
Track tension is one of the most critical variables in achieving optimum undercarriage life.
The undercarriage life expectancy of a compact track loader is subject to many variables to predict with any degree of accuracy. But you can measure its life against various baselines to get an idea if costs are running out of control.
Mike Fitzgerald, Bobcat loader product specialist, estimates the average life of rubber tracks to be between 1,200 and 1,600 hours. However, it depends on the operating conditions and the application.
"Contractors who work on streets and improved surfaces, and rental-type machines, will have tracks last in the 800- to 1,200-hour range. Some severe-duty applications that are more abusive to tracks may get less than 800 hours," he points out. Contractors performing only earthwork may see track life in the 1,600- to 2,000-hour range. "I recently looked at a machine that had just under 1,800 hours of use. The tracks were only 50% worn, but the loader had not done a significant amount of work on streets or parking lots. That machine is used for backfilling dirt around building sites."
According to Cameron Stejskal, product specialist, Terex Construction Americas, "There are four main factors that affect undercarriage wear: application, underfoot condition, operating technique and maintenance practices. Wear and tear is directly affected by operator knowledge and the operating conditions."
The undercarriage is the most costly part of any tracked machine; it can make up almost 20% of its purchase price and nearly 50% of maintenance costs over its service life. "Such valuable components should never be neglected," Stejskal emphasizes. "It is extremely important to keep the undercarriage clean. This helps ensure longevity of components and keeps operating costs down."
"The ability to maximize undercarriage life, or minimize owning and operating costs, is largely up to the operator," says Kevin Coleman, senior marketing project engineer for Caterpillar's Building Construction Products Group. "The operator controls approximately 60% of the owning and operating cost of a rubber track loader through his operating techniques and maintenance practices."
"A well-trained operator can reduce maintenance costs by 'preventive operation'," says David Steger, national product and training manager, Takeuchi. "Making wider turns, controlling slippage, understanding the surface you are operating on and regulating the load all contribute to longer undercarriage life."
Many operators run compact track loaders as if they are skid steers. "Skid-steer operators do a lot of counter-rotating and spinning of tires to get the bucket filled to the maximum capacity," Stejskal notes. "Compact track loaders have enough traction that the tracks do not need to spin to fill the bucket. If the tracks are spinning and the machine is staying still, your track life will be greatly reduced.
"This comes into effect even more when you operate on a rough underfoot condition," Stejskal continues. "When you counter-rotate with a compact track loader, especially in loose underfoot conditions, a lot of material is ingested into the undercarriage. Three-point turns, rather than spinning or counter-rotating, will save on undercarriage wear."
Aggressive operation may help get the job done faster, but it can also increase the rate of wear and overall operating costs, says Coleman. For example, making a quick change in travel direction by counter-rotating can result in material buildup in the undercarriage, which may cause unnecessary wear on the tracks and undercarriage components.
"Turning without counter-rotating may take more time," he acknowledges, "but can extend the service life of undercarriage components. Only counter-rotate when necessary."
While a compact track loader is ideal for use on slopes, improper operation across slopes can cause faster wear to undercarriage components. "Going across the slope puts side loads on rollers, idlers and tracks," Fitzgerald notes.
"You can reduce unnecessary side loading wear by operating up and down a slope -- rather than across -- whenever possible," Coleman states.
Avoid working along transitions -- any place where you may encounter a sudden change in slope or elevation. "Transitions can result in one of the machine's tracks not being fully supported by the ground," says Coleman. "Without the full support of the ground, the track and roller wheels are subjected to side stress that could lead to track derailment or damage."
Avoid turning on transitions whenever possible. "A curb or ledge can also be considered a transition," says Coleman. "If you must travel over transitions, do so with the machine 90° to the transition."
"When operating the machine, try to keep the full length of the tracks in contact with the ground," Fitzgerald advises. "Do not raise the front of the machine with the bucket because that lessens traction.
"If you climb over a curb, go directly over it in a forward or reverse motion," he adds. "If you hit it at an angle, there is the potential for damaging the tracks and creating additional costs."
Also take precautions when working on improved surfaces, such as asphalt or concrete. "Our suggestion is to put material such as sand or dirt between the surface and the track to make the loader easier to turn, and then clean up that material when you are done," says Fitzgerald.
Track maintenance -- which includes proper tensioning, cleaning and inspection -- should be done on a regular basis. "Follow the schedule in the operator's manual," says Steger, "but undercarriage inspections should be more frequent when in muddy or abrasive conditions."
Check for uneven wear. "The components are designed to wear evenly," says Stejskal. "If some components wear more quickly than others, it can affect the productivity and wear all of the components."
Keeping the machine clean will make it easier to identify potential problems, and decrease wear due to debris lodged between components. Cohesive and abrasive materials such as mud, clay and gravel should be cleaned out as often as possible.
"At the end of the day, knock away any debris that's accumulated in the tracks, and then while the machine is still warm, wash it down to get rid of any remaining materials that could cause corrosion or contamination," says Stejskal. "The end of the day wash-down process is a good time to remove embedded foreign objects from the tracks and lubricate all moving parts. The daily wash down is also an excellent time to look for any loose, worn, cracked, bent or missing components."
"Check the track for cuts, punctures or tears," advises Steger. "Sprockets and rollers should be inspected to ensure they are in good condition with no damage, excessive wear or 'flat spotting,' which may be an indication of material buildup or bearing seizure. Any oil leakage from rollers, hoses or travel motors should be repaired immediately. It is recommended to replace the sprockets each time new tracks are installed."
Check track tension regularly. Running too tight or too loose creates problems. "If you run tracks too tight, you will use more power and cause premature wear because they are tighter and there is more friction," notes Fitzgerald. "If you run in sand or small granular material, a tight track will force that material between the metal parts and wear on them."
It is best to err a little on the loose side. "If you want to run to one side or the other within the specification, our recommendation would be to run them slightly on the loose side, because running on the tight side really doesn't do much for you," says Fitzgerald. "If they are loose, the material will shed better. However, if they are way too loose, the tracks will come off. You can go too far."
He admits that track tension is not a perfect science. "We have customers in the Southeast where there is a lot of sand, and in some of the mountain areas where there is small, granular rock, who run their machines slightly loose as compared to our recommendation," he notes.
The operating environment can be a contributing factor in premature component wear. "For rubber tracks containing steel imbeds and cords, salty environments can contribute to accelerated track wear due to the corrosive nature of salt and airborne water vapor containing salt," says Coleman. Remove salt deposits by washing at your earliest opportunity.
Just by training the operators, cleaning the tracks, maintaining the proper tension and inspecting on a regular basis, you can reduce operating costs significantly. "Things as little as doing three-point turns instead of counter-rotating, and taking extra time at the end of the day to clean the undercarriage, add up tremendously," says Stejskal.