Top Operators Can’t Defeat JCB’s PowerBoom

April 4, 2011

JCB skid steer and compact track loaders have earned a measure of product distinction in the marketplace with their PowerBoom design, which uses a single boom arm on the right side of the machine. The company’s sales pitch for the PowerBoom is simple and sensible: Compared with conventional twin-boom-arm designs, the PowerBoom allows operators to safely enter and exit the machine from the left side—no climbing over front-mounted work tools—and once in the cab, visibility is noticeably better.

JCB skid steer and compact track loaders have earned a measure of product distinction in the marketplace with their PowerBoom design, which uses a single boom arm on the right side of the machine. The company’s sales pitch for the PowerBoom is simple and sensible: Compared with conventional twin-boom-arm designs, the PowerBoom allows operators to safely enter and exit the machine from the left side—no climbing over front-mounted work tools—and once in the cab, visibility is noticeably better.

When JCB recently introduced the first models of its New Generation Series, the PowerBoom and the company’s Dieselmax engine were among only a few features that made the cut from the previous Series II design. 

“It’s a clean-sheet-of-paper design that uses 38 percent fewer parts than the Series II,” says George Chaney, product manager for JCB’s skid-steer and compact track loaders. “New Generation models are designed to accommodate today’s markets.”

Recognizing that these new models were significantly different from their predecessors, Construction Equipment asked JCB for the loan of a New Generation machine in order to get a close look at its features and capabilities. We told JCB that we’d like to get opinions about its new machine from some of the best operators we know, instructors for the Apprenticeship and Skill Improvement Program at Local 150 (International Union of Operating Engineers).

The company graciously responded, delivering to Local 150’s facility in Wilmington, Ill., a new 330 skid-steer, fresh from JCB’s Savannah, Ga., factory and fitted with pretty much everything in the price book—enclosed cab, servo-controlled joysticks, heated air-suspension seat, air-conditioning, high-flow hydraulics, two-speed travel, parallel-lift linkage, hydraulic coupler and JCB’s Smooth Ride System. The 8,700-pound 330, largest model in the new range so far, produces 92 horsepower (gross) from its TC-68 Dieselmax engine and has a rated operating capacity of 3,300 pounds.

So, on the appointed day in early March, we convened in Wilmington—our operators for the day, Local 150’s Todd Peterson and Kevin “Zip” Ackert; JCB’s Chaney; Karen Guinn, JCB’s PR and communications manager; plus a couple of CE editors.

The day was cold, with a raw wind that whipped around a large pile of water-soaked, partially frozen crushed limestone, where the 330 did some basic digging and load-and-carry runs. The weather was more agreeable, however, when we took the 330 into the facility’s indoor arenas, where Peterson and Ackert used the 330 with forks and a number of attachments.

Does this really work?

First off, since Peterson and Ackert were unfamiliar with JCB skid-steers, we asked Chaney to give us a walk-around of the 330 and to touch on the basic aspects of the New Generation design. First stop on the tour, of course, was the machine’s most obvious feature: the PowerBoom.

Remember, now, Peterson and Ackert have been running equipment for decades, and they’ve pretty much decided what works and what doesn’t. You could see by their expressions, as Chaney talked about the PowerBoom, that they were probably thinking: “This thing defies the laws of physics.”

Chaney explained that the PowerBoom has been used on these small JCB machines for more than a decade, and its design is based on that for the company’s Loadall telescopic handlers. The PowerBoom, according to Chaney, uses some 20 percent more material in its fabrication than is used in both boom arms of most conventional designs, and its linkage pins are three times larger in diameter than those typically found on skid-steers.

Peterson and Ackert, however, seemed unconvinced.

“So, when you run the bucket into a pile or do excavating in hard material,” asked Peterson, “isn’t there a problem with the entire boom and bucket trying to twist to the left—toward the unsupported side?”

Chaney said he gets this question a lot; the only answer, he said, is to give skeptics the key and tell them: “Try to break it.”

New models, new ideas

So far, the New Generation line includes four skid-steers and three compact track loaders, all vertical-lift, which is a new feature for JCB and of the company’s own design. A total of 18 New Generation models is on the way, with a mix of wheeled and tracked machines, as well as a mix of vertical- and radial-lift linkages.

During the New Generation design phase, said Chaney, engineers were encouraged to keep an open mind about machine features, and the exercise resulted in some new approaches to routine skid-steer design.

For example, he said, one engineer questioned why enclosed-cab skid-steers have steel mesh on the side windows. Telescopic handlers aren’t so equipped, he reasoned, and by using laminated glass, the mesh could be eliminated. Says Chaney: Operators now have “visibility they’d never seen before.” Canopy machines still have mesh on the right side, but the left has just a partial screen for improved visibility on that side.

Hydraulic refinement

Among the significant refinements in the New Generation design, Chaney told us, is increased pressure and flow for greater hydraulic capability. Our 330, for instance, delivered 35.7 gpm at 3,335 psi from its optional high-flow system, producing nearly 70 hydraulic horsepower.

A complete redesign of the hydraulic system eliminated 25 percent of the connections, compared to Series II, said Chaney, and connections now use O-ring face seals, which replace British Standard Pipe fittings. Auxiliary lines terminate conveniently at a quick-connect panel at the boom head, including a case drain and a 14-pin connector for electric functions at the attachment.

Present New Generation models are fitted with hydraulic-servo, multi-function joysticks (including a float detent), and the left joystick/armrest console tilts rearward to permit unimpeded access into the cab, while also serving as a safety interlock.

A new hydraulically driven cooling fan is thermostatically controlled to run only at speeds required to provide optimal cooling. The new fan saves fuel, said Chaney, and helps reduce sound levels in the cab to aound 76 dB(A), down from 85 dB(A) in Series II models.

Compared with Series II models, the large-platform New Generation machines have a significantly longer wheelbase (48 versus 44 inches), which, said Chaney, makes a notable difference in the ride quality and stability of the new models. The chain case has been redesigned, featuring heavier chains that require no adjustment after tensioning at the factory. In addition, the design of the axle towers also allows easy access to the case interior, he said, and a universal bolt-hole pattern allows switching wheel types.

Cabs for New Generation models are some 33 percent larger than those of the Series II, and the new cabs are sealed and pressurized to keep interiors cleaner and quieter. Instrument panels have been moved to the upper front corners of the cab, and the throttle is now electronic—using a dial to set the engine speed preferred by the operator, coupled with a foot throttle for accelerating upward from that setting.

A trigger in the left joystick selects travel range (with two-speed travel), as well as creep speed. The standard creep-speed system allows the machine to travel slowly when the engine is at high rpm, thus generating high oil flow for effectively driving hydraulic attachments, while also providing optimal control. The system permits the operator to make travel-speed adjustments in 50 increments, starting at 3.6 mph (half the low-speed setting) and adjusting downward.

Chaney impressed his small audience during the walk-around when he reached into the 330’s cab with a ratchet and 24-mm socket, quickly removed two nuts from cushioned studs at the rear, then tipped the cab forward. The machine’s entire mid-section was accessible. Opening the 330’s wide tailgate gives access to routine service points and to its new cooling package with a side-by-side radiator and hydraulic-oil cooler. Placed at the top of the engine compartment, the package slides out and tilts up for cleaning.

Views from the seat

When the 330 arrived, it was fitted with a landscape bucket, having a capacity of about a cubic yard. The first exercise was to use the 330 in a tough stockpile operation—in the heavy, wet, icy limestone pile already noted. When both operators had used the 330 in the pile and had made a few load-and-carry runs, we asked for first impressions.

Both operators were quite taken by the left-side door, saying that the entry door and general layout of the cab is much like that of a hydraulic excavator. Both were equally impressed by the 330’s hydraulic power and tractive effort.

“The breakout force of the bucket is just outstanding,” said Ackert, “more like a rubber-tired loader than a skid-steer. You can walk right into the pile without hesitation. I tried to use it in the frozen stuff as much as I could to see if I could stop it, but it’s an aggressive machine. And there’s not a hint of bucket twist.”

Peterson’s reaction was similar: “It doesn’t feel as if you’re in a skid-steer—it’s a whole different experience. This material is really heavy, but the machine gets after it with no problem.”

And the stability of the loader linkage?

“When I went into the pile,” said Peterson, “I admit I  was looking for the left side to sag, but it doesn’t. You do have the first impression that it can’t be this solid, but it is. I’m impressed.”

The platform is very stable,” said Ackert. “Even when I was in the wet stuff with a full bucket and I stopped short, it would dip forward a bit, but not nearly as much as I would have thought.”

Other first impressions?

“The visibility—you can pretty much see 360,” said Ackert. “Because it doesn’t have a torque tube across the back to connect the boom arms, you can look up in the rear-view mirror and see behind you.

“With all the glass around you, the peripheral vision is excellent.”

Both operators did load-and-carry runs with the Smooth Ride System (ride control) switched off, then on. The system uses a nitrogen accumulator in the boom’s lift circuit to cushion the bounce of the bucket when traveling with a load. Both Peterson and Ackert were already fans of ride control on skid-steers, so they considered this option a worthwhile investment for users who can benefit from it. Says Peterson: “Without ride control, you can lose half the material in the bucket.”

Lift stability and self-leveling

Our 330 was equipped with parallel-lift (self-leveling) linkage that keeps the bucket or forks level as the boom rises. According to Chaney, JCB’s new parallel-lift system uses hydraulic action—not mechanical linkage—to achieve self-leveling. We attached forks, and the operators maneuvered on the inside arena’s concrete floor with a couple of reasonably heavy test pallets.

“It has great stability,” said Peterson. “I like the fact that you don’t have an arm on the left side, because it gives you a better view of the load.”

Ackert switched off the self-leveling feature and manually controlled the load on a couple of lifts.

“If you don’t use the parallel lift,” he said, “then the way the linkage is designed, it looks as if the forks are tilted slightly forward. They’re not, but it’s one of those things you’d have to get used to.”

Peterson took note that the parallel lift feature worked only during boom lift, not when the boom is lowered.

“It would be handy to have the parallel lift work in both directions,” he said. “I know that most manufacturers have eliminated that feature on the lower cycle, but it would useful when you’re unloading a truck. Operators unfamiliar with the system would need to be told that it doesn’t work in the lower direction.”

Peterson told us that there are blind spots when handling a load with the 330, but that poor visibility at some point in the lift is a problem with all skid-steers.

“No matter what skid-steer you’re using with forks, there’s going to be a blind spot. But this cab is large enough that you can position yourself to get a good line of sight and see around it. Most skid-steer cabs would be too small to do that.”

In the dirt

We next moved into the dirt arena, which is, literally, slightly larger than a football field. It was a busy place, as the operator-training season is in full swing at the Local, but we had ample room to run a landscape rake and a six-in-one bucket. Since the rake was capable of running with up to 40 gpm hydraulic flow, the operators used the 330 in high flow. Both commented on the power of the auxiliary system and its single-lever controllability.

When we installed the six-in-one bucket, the operators found a particularly hard spot in the arena’s clay and used the bucket to excavate, then opened the upper jaw and used it as a dozer blade. As in the limestone pile, both were impressed with the 330’s solid digging characteristics.

“Considering that the bucket had no teeth or side cutters,” said Peterson, “the machine moved in without hesitation—and this clay is really hard.”

Final thoughts?

“I guess I’m convinced that you can’t tweak that bucket,” said Peterson. “I tried. You look at the design, and you think that the boom is going to give, but it doesn’t. The only features I’d like to see are self-level on the way down and a side-light kit [which is available]. So, if you want to have a skiddy test, I’ll run this one.”