Yanmar, a company that soon will celebrate 100 years in business, is betting that the compact dimensions, versatility and performance of its new CBL40 will appeal to buyers who find full-size backhoe-loaders frequently too big for the job, or who are looking for a bit more application flexibility than even big skid-steers or compact wheel loaders can provide. The CBL40 is, at heart, a sturdy backhoe-loader. But with a universal coupler up front, and with a backhoe that can be removed to allow using attachments with the machine’s optional three-point hitch or PTO shaft, the CBL40’s potential is significantly expanded.
Construction Equipment had the opportunity for a close look at the design and performance of the new Yanmar in mid-May, when the company loaned us a CBL40 that was on a demonstration tour in northern Illinois. We, in turn, placed the machine in the capable hands of Frank Bogden, an instructor/operator at Local 150’s (International Union of Operating Engineers) Apprenticeship and Skill Improvement facility in Plainfield, Ill.
Bogden used the machine to trench in some tough rocky fill, backfilled the cut, loaded trucks with crushed limestone, took the CBL40 on a couple of load-and-carry runs, then switched the bucket for a set of forks to handle lengths of 8-inch ductile iron pipe. He and Local 150 instructor/technician Dale Brown then separated the machine from its backhoe (in the field) to check the difficulty of doing so and, in the process, gave us a look at the optional category-1, three-point hitch installation and the optional PTO.
Overall, Bogden spoke highly of the CBL40’s design and performance, but did have a number of suggestions for making the machine more accommodating and useful from the operator’s point of view. Judging from the way several visitors from Yanmar listened and took notes during the evaluation, however, we’d guess that most of Bogden’s suggestions soon will be incorporated.
On site from Yanmar to give us a walk-around introduction to the machine and to answer questions were Takayuki Fujiwara, marketing manager; Bill Gearhart, assistant marketing and product manager; and Lee Haack, regional sales manager.
Quick CBL40 design tour
Even though Yanmar has deep roots in the agricultural business, the company strongly makes the point that the CBL40 is not a converted farm tractor. It is, says Yanmar, a machine designed exclusively for the construction industry, and one that builds on the structural durability of the company’s wheel loaders and on the hydraulic sophistication of its compact excavators.
The backbone of the new machine is an integral, one-piece frame designed to handle digging and loading forces at either end. A three-cylinder, turbocharged Yanmar diesel engine, generating 35.4 net horsepower, drives a closed-loop, load-sensing, two-speed “hydro-mechanical” propel system that, in turn, powers a mechanical gearbox that delivers its output to the conventional front and rear axles via drive shafts. An in-cab control disconnects the front axle for sustained high-speed travel.
The machine’s implement hydraulic system, which draws oil from a reservoir separate from the drive system, employs two, variable-displacement, axial-piston pumps. A lever in the cab’s right console switches the configuration of the hydraulic system between loader and backhoe operation, and in the backhoe position, ensures constant speed for the digging arm when another function is also engaged.
At the loader end, the CBL40 is fitted with a 70-inch-wide general-purpose bucket, but a universal-style quick coupler allows the use of size-appropriate skid-steer-loader attachments. Piping for auxiliary hydraulics to the front (as well as to the backhoe) is optional, but the auxiliary valve sections are already in place. The loader mechanism uses slab-steel lift arms and a geometry that allows parallel lift and automatic self-leveling.
Working the CBL40
The CBL40 has a swing-around seat (not a flip-over type) for switching from the loader to the backhoe position. Backhoe controls are two mechanical (not pilot operated) joysticks that can be configured in either a backhoe or excavator pattern by switching pin positions in the linkage at the main valve. The linkage is easily accessible through a panel at the rear of the operator’s compartment and, says Yanmar, changing patterns is accomplished in just a few minutes.
When we asked Bogden which pattern he preferred, he said that either would be fine, and he went to work trenching in the wet, cobble-laced clay at the site.
After this exercise, he had a few suggestions for Yanmar. First, give the seat vertical-adjustment capability. The seat is comfortable enough, Bogden said, but some operators prefer to sit higher. Also, make provisions for pinning the outrigger pads in place, because they sometimes flipped from the dirt side to the smooth-pavement side during repositioning, requiring him to exit the cab to remedy the problem. And another helpful change, he suggested, would be a backhoe lock that’s easier to manipulate from the seat, because the lock’s present configuration requires the operator to lean well forward from the backhoe position to reach the handle.
Aside from these observations, Bogden was quite complimentary about the CBL40’s backhoe performance, especially its hydraulics.
“Plenty of power and very responsive. The system does a good job of allowing you to simultaneously arm in and boom up. The controls have a good, smooth feel. I was concerned at first that since the machine has a hydrostatic-type drive, it would be difficult to reposition, but it rolled easily when I pushed back.”
Bogden particularly liked the good visibility into the trench — the result, he said, of Yanmar’s keeping the backhoe’s boom narrow.
Although Bogden said he didn’t have that much experience with hydrostatic-drive machines, he liked the way the CBL40 pushed strongly into the spoil when backfilling the trench. But what the machine could really use, he said, is a simple “bucket-level” indicator somewhere on the loader linkage.
After making a number of short-cycle passes between the crushed-limestone stockpile and a small truck, he commented favorably on the machine’s speed and its hydraulic capability when handling heavy material. Also noted were the CBL40’s good dump height and reach — “enough reach to easily place loads in the center of the truck.” Also, he said, he liked the machine’s controllability when approaching the truck.
With the bucket full of crushed rock, Bogden took the CBL40 on several circuitous routes to test its load-and-carry capability.
“The machine handles well — it feels very stable, and the turning radius is tight, which makes it very maneuverable. Although I didn’t take the machine into any really rough areas, the ride quality seemed fine, and the steering and brakes were responsive — no objections there.”
As a final exercise, Bogden swapped the bucket for a set of pallet forks, took the machine through some moderately sloppy ground to reach the pipe stockpile, then loaded and maneuvered with long sections of pipe.
“I was impressed with the good visibility to the load,” he said. “Granted, the loads we were handling probably weren’t much of challenge, but the machine seems to have plenty of lifting power, and the hydraulics, again, are quite smooth. And the parallel-lift feature is always a plus.”
We also had in mind to use the CBL40 to do craning with the backhoe, but Bogden noted that the machine had no lifting eye on the bucket. He suggested that the addition of that item would be a handy feature — which would encourage operators to rig loads in a safe manner.
So, Frank, any final thoughts about this compact Yanmar?
“I think, overall, it would be a very handy piece of equipment for a contractor. It has a lot of versatility built in, especially with the three-point hitch. It’s a good ‘multi-tasker’ — a well-thought-out machine.”
When we asked product manager Scott Owyen at Terex to list what he considered to be significant recent technical advances in backhoe-loader design, he placed the Tier-II engine at the top.
Backhoe-loader buyers may well overlook the Tier-II engine’s contribution to the machine’s overall refinement, and that’s understandable. The engine’s use, after all, has been legislated, not developed primarily to make backhoes more valuable to the user. But as it turns out, these environmentally friendly engines, which are running with fairly stringent standards for nitrogen-oxide and particulate-matter emissions, actually deliver practical benefits.
Says Owyen of the Tier-II Perkins engines in Terex backhoes: “We’re finding that these engines have increased horsepower, more torque, better fuel economy, lower sound levels and, of course, reduced emissions. Plus, maintenance intervals have been extended.”
On the fuel-economy issue, CE field tests of Tier-II-compliant machines (of all sorts) have turned up fuel-efficiency improvements (the amount of material moved per gallon of fuel) ranging from 5 to 30 percent. For example, in a recent CE field test of a JCB New Generation 214 backhoe-loader against its predecessor model, the new machine averaged 10 percent better fuel-efficiency when trenching in moderately difficult conditions.
Fuel is not a big concern for every backhoe user, of course, as long as the machine gets through the workday without a visit from the fuel truck. Many users, however, are acutely aware of rising operating costs and are looking for every penny they can save. For this group, the apparent efficiency of Tier-II engines, coupled with their generally longer service intervals, may yield significant savings.
Pilot controls
Every backhoe operator has a favorite control system, whether a two-lever arrangement with the boom on the left and the dipper on the right (or vice versa), a three-lever system with foot swing or a four-lever setup. What these systems have in common is mechanical linkage that connects the levers to the backhoe’s control valve.
If it’s been a while since you’ve looked at new backhoe, however, you’ll find that the majority of manufacturers have added a new system to the mix-pilot controls. These new controls, which may be available for all or just select models in a manufacturers line, typically take the form of joystick controllers mounted in consoles adjacent to the seat.
When you move the joysticks, you’re not pushing and pulling rods and bellcranks, but instead, simply shifting spools within a small hydraulic “pilot valve” at the base of the levers. Oil flow from the pilot valve is directed to the ends of the spools in the main valve, thus supplying the effort to shift the spools.
The advantages of pilot controls, say manufacturers, include considerably reduced lever effort, a more comfortable operating position (less leaning forward in the seat), and a better view into the trench, since the lever console at the operator’s feet is eliminated. And, more often that not, pilot-control systems have a lever or switch that allows operators instantly to configure controls to their liking by switching the boom and arm functions side-for-side.
Yes, some operators object to pilot controls, saying that they jeopardize the “feel” of the backhoe-that is, the ability to sense through the control levers what the bucket is encountering in the trench. Perhaps it’s just a matter of becoming accustomed to the slightly different inputs that new system delivers to the operator’s hands.
Hydraulic choices The issue of backhoe “feel,” of course, also extends to basic hydraulic systems. Some operators swear that the widely used open-center system is best in this regard. “Open-center” means simply that the control valve is always open to receive all the oil flow that one or more fixed-displacement gear pumps can deliver. If the oil isn’t needed, it returns to the reservoir.
Open-center systems, say operators who love them, not only clearly communicate what the bucket is doing in the trench, but also are particularly responsive, since the system’s full volume of oil flow is, potentially, always available to satisfy hydraulic demands. Manufacturers using these systems claim further advantages, namely, the use of less expensive, more forgiving (of contamination) gear pumps, overall design simplicity and simpler, less expensive repair.
On the other side of the fence, so to speak, are operators who favor closed-center hydraulic systems. These systems typically use a variable-displacement, axial-piston pump that works with the control valve to produce only the volume of oil that’s actually needed for the task at hand. Because the pump can regulate its output independently of engine speed, and because the system has the ability to sense loads in the various hydraulic circuits, the pump continually and automatically adjusts output volume for peak efficiency.
John Deere uses both open- and closed-center systems in its backhoe range, with the latter system fitted to the larger 410G and 710G models.
“The systems on the larger units allow more precise combined-function metering,” says Bob Tyler, product marketing manager for Deere’s backhoe line. “The cost goes up, of course, and according to some, the ‘feel’ goes down. But the system provides definite advantages: flow goes where it’s needed, not where the machine chooses to send it, and it saves fuel. And, I’ll add that I’ve never heard the ‘lack-of-feel’ complaint from a customer.”
Like Deere, Volvo also uses both system types¡ªan open-center in its BL60 model, and a closed-center in the larger BL70. According to product specialist Bill Sauber, however, the BL60 has “flow-sharing” ability built into the valve, a feature that automatically maintains pressure and flow for each function and enhances multi-function operation.
Terex uses what might be called a hybrid system, closed-center in design, but employing twin gear pumps. According to the company, the system essentially combines elements and benefits of both the conventional open- and closed-center designs, including load-sensing capability and the ability to smoothly blend multiple functions.
Truth be told, you’ll find it difficult to go wrong with any of the hydraulic systems offered on today’s selection of backhoes. Some buyers may be swayed one way or the other, however, based on their perception of a particular system’s value in their specific applications.
Couplers and comfort
Case’s Rusty Schaefer notes that backhoe buyers increasingly are specifying couplers for new machines to increase utility. Case, as do many backhoe builders, offers both a mechanical and hydraulic coupler for both ends of the machine. In addition, says Schaefer, Case offers an optional “integrated” hydraulic coupler on its 580 and 590 Super M models. As an integral part of the dipperstick, the coupler is designed to eliminate attachment offsets, to add no weight and to preserve digging forces.
Komatsu’s Mike Oliver also sees more buyers opting for couplers as they look for ways to make their machine investment more productive. He sees multi-purpose buckets as the leading front attachment, followed by forks and brooms. On the backhoe end, says Oliver, different-width buckets, hydraulic hammers, compaction wheels and plate compactors are popular tools.
Says Terex’s Owyen: “Even rental yards are now ordering machines with couplers and attachments.”
A final refinement that’s most noteworthy on today’s backhoes is the comfort and convenience of the operator’s environment. Cabs are larger, have more glass, and interior appointments are automotive-like. Available features such as pilot controls, suspension seats, ride-control and climate-control make long days not feel so long. And the wider availability of powershift and auto-shift transmissions makes the ride even more pleasant.
“Today, productivity is taking the direction of operator comfort,” says Deere’s Tyler. “Comfortable operators stay in the seat longer and get more done.”
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