Pros Test Wacker Neuson 750T’s Ambidextrous Design

Nov. 8, 2011

Is it really three machines in one? According to Wacker Neuson, the 750T—with its telescopic-boom, all-wheel steering and coupler flexibility—has the potential to work as a wheel loader, rough-terrain forklift and an attachment-handling skid-steer. Says Tom Petersen, product development specialist for Wacker Neuson, the 750T has a “universal” design—it’s a machine, he says, that handles many jobs well with a minimum of compromise.

Is it really three machines in one? According to Wacker Neuson, the 750T—with its telescopic-boom, all-wheel steering and coupler flexibility—has the potential to work as a wheel loader, rough-terrain forklift and an attachment-handling skid-steer. Says Tom Petersen, product development specialist for Wacker Neuson, the 750T has a “universal” design—it’s a machine, he says, that handles many jobs well with a minimum of compromise.

To get a close look at the 750T’s ambidextrous character, Construction Equipment asked Wacker Neuson for the loan of a machine that we could place in the expert hands of professional operators at Local 150’s (International Union of Operating Engineers) training facility in Wilmington, Ill. A new 750T soon arrived in Wilmington, together with two buckets (light material and multipurpose), large rotary broom, set of forks and a skid-steer adapter/coupler. We supplemented these attachments with a grapple bucket, auger and trencher borrowed from Local 150.

Jeff Cromer and Nick Jorgensen, both instructors in Local 150’s Apprenticeship and Skill Improvement Program, then spent the better part of an early-September day with the 750T, using these work tools to assess the machine’s versatility and potential limitations. Wacker Neuson’s Petersen and trainee Max Walchshofer were on hand to answer questions.

Design basics

Included in Wacker Neuson’s extensive product offering is a range of compact construction machines that takes in powered dumpers, small excavators and compact wheel loaders with both articulated and four-wheel steering. Within the four-wheel-steer range are two conventional-boom models and the 750T, with its distinctive, center-mounted telescopic boom that can raise the height of the bucket pivot pin from 141 to 183 inches.

The 750T uses a 60.3-horsepower, water-cooled Deutz diesel to drive the variable-displacement pump in the machine’s hydrostatic propel system. The hydrostatic system’s hydraulic motor powers a gearbox, which in turn powers conventional planetary axles that provide an automatic self-locking (torque-proportioning) feature that can transfer 45 percent of the power between wheels to improve traction. A floor-mounted inching pedal allows travel speed to be controlled independently of engine speed and applies a shaft-mounted disc brake when depressed beyond the point of neutralizing the drive system.

Stacked with the hydrostatic pump is an 18.8-gpm gear-type pump that handles the 750T’s implement- and auxiliary-hydraulic systems. Auxiliary-system couplers are neatly positioned in a panel on the boom’s left side, together with an electrical connector for attachments having electrically driven functions.

A joystick at the operator’s right controls lift and tilt functions, has a thumb wheel for selecting travel direction, and provides push buttons for neutralizing the transmission and for extending and retracting the telescopic boom. An adjacent lever controls both the locking pins in the 750T’s hook-and-pin type coupler (when activated while holding in a switch), as well as the auxiliary-hydraulic system’s third spool, which provides continuous flow when the lever is pulled into a detent position.

As an option, the 750T can be fitted with a hand throttle and a low-speed-control lever, which allow setting both engine speed and ground speed without having to keep continual pressure on the accelerator and inching pedal. The hand lever combination is helpful, says Petersen, when certain attachments, such as a trencher, are being used.

Big-bucket test

In what turned out to be an unintentional test of the 750T’s loading capabilities, the first task the machine took on was loading an extremely heavy crushed-rock material from a stockpile into a tandem-axle dump truck. But instead of using the 0.98-cubic yard general-purpose bucket that we expected, the 750T used the 1.25-cubic yard light-material bucket that arrived with the machine. The operators hooked on to the big bucket and cut the 750T no slack, coming out of the pile with heaping loads.

“The bucket was probably larger than you’d want for consistently working in material this heavy,” said Cromer, “but the machine handled it well. The hydraulics are strong and the stability is fine. I thought a couple of times it was getting a little light in the back end, but the load indicator stayed in the green.”

 (The 750T is equipped with a load-indicating system that senses weight on the rear axle, then reports to an in-cab monitor that has six lights—four green, one yellow and one red—that illuminate successively as load on the rear axle lessens.)

“I really like the close turning radius and the design of the inching pedal,” said Jorgensen after an initial run with the large bucket. “You can bring up engine speed for fast hydraulics, but keep ground speed at just the level you want. It gives a lot of control. And for a small machine, the cab feels roomy.”

Jorgensen also experimented with the telescopic boom when dumping into the truck.

“A nice feature that would let you load larger trucks,” he said. “You have to get used to how much the boom will telescope when you press the buttons, and I thought the telescopic action was a bit jumpy. But it’s just one of those quirks that all machines have; you get used to it and you’re good to go.”

(Petersen explained that the telescopic action of the boom is not hydraulically proportional, that is, it’s an on/off system that can’t be feathered and does require some experience to run smoothly.)

We did notice that both operators backed out of the pile the first couple of times with the turn signal blinking—the result of trying to use the stalk to shift travel direction, a feature many wheel loaders incorporate.

“The design is obviously intended to let you keep your right hand on the joystick and your left on the steering wheel,” said Jorgensen. “Great idea—again, just takes some time to make the adjustment.”

Forks, multipurpose, and tight turns

Cromer then hooked on to the forks and used the 750T in the Local’s forklift training area, where placement racks of various heights and steel pallets with various weights attached are used to test student skills and machine capabilities. Overall, Cromer was impressed with the 750T’s capabilities.

“The machine drives just like an off-road forklift,” he said. “It’s a little stiff in the front, but that’s just a matter of getting used to it. It’s very stable as a fork machine. My only criticism is, that with the boom being right in the center of the machine, the view to the forks is somewhat restricted. You have to maneuver in the cab to see the tips. I also think it needs an indicator that tells you when the forks are level—or maybe a detent in the control lever that levels the forks.”

Next we attached the multipurpose bucket with a 0.85-cubic yard capacity and again asked the operators to load from the stockpile of heavy material. Both agreed that for this material, the smaller bucket was a better fit, and that the 750T could be quite productive using it. Both also used the bucket as a dozer blade, but reviews were mixed.

“The multipurpose is definitely a good tool,” said Cromer. “I’ve used it as a grapple to set manholes—the frame, cover and all. It’s handy. But as far as trying to grade with the multipurpose as a blade on a rubber-tired machine, you’re probably better off just using the bucket.”

Jorgensen, on the other hand, thought that the blade configuration worked moderately well.

“The blade is a nice feature. The machine pushed loads well with no wheel spin, and control was good. I expected to be bouncing around a bit more, but it’s really a pretty good ride.”

As a further test of handling and stability, Cromer took the 750T up a steep berm with a full bucket and then did a 180-degree turn to come down.

“It’s definitely stable,” said Cromer, “and it’s got power. I can’t see anyone trying to climb anything steeper than this, and it handled it well. I doubt you could make that one-eighty turn on a slope this steep with an articulated machine.”

Attachments

The 750T picked up the universal (skid-steer-type) attachment bracket and then, in turn, the attachments—rotary broom, auger, grapple bucket and trencher—as easily as might have a skid-steer.

Petersen explained that our 750T was equipped with four momentary circuits to handle ancillary functions such as angling snow blowers or rotary brooms or controlling a broom’s sprinkler system. Also, he said, the 750T uses a back-pressure valve in the auxiliary circuit to maintain acceptable lift and tilt functions when using an attachment.

Without going into all the details, we can summarize by saying that both operators were favorably impressed with the 750T’s attachment-handling capability. Two demonstrations do stand out, however—the trencher and grapple bucket.

The 750T is designed to work optimally with a 3-foot trencher, but Local 150 had only a 4-footer. Nonetheless, the machine did not hesitate with the larger tool.

“It handled the trencher better than I’d have thought,” said Cromer. “But you really need the hand throttle/slow-speed option for an application like this—so you could set engine speed and ground speed without having to constantly control those functions with the foot pedals.”

Jorgensen then used the grapple bucket to lift and maneuver a crane mat, which was made from maybe half a dozen 12x12 timbers about 20 feet long. The relative ease with which the 750T handled this heavy, cumbersome load impressed all assembled.

“I’d have thought the machine wouldn’t have had enough hydraulic power or stability to handle a load like this,” said Jorgensen, “but it lifted strongly, and I had only two green lights on the load indicator.”

Summing up

At the end of the day, we sat down with Cromer and Jorgensen and asked for their overall impressions of the 750T.

“With the quick-attach and the telescopic boom, it’s definitely a versatile machine,” said Cromer. “The stability is good, and it appears to have the capability to run a fairly broad range of skid-steer attachments—that’s a big plus. The turning radius gives almost skid-steer-like maneuverability. And it’s comfortable—good seat and overall good controls.”

“I liked the visibility from the cab—it’s wide open and you can pretty much see three-sixty,” said Jorgensen. “It’s a comfortably sized machine. And I’m still impressed that you can step hard an both the accelerator and the brake to get maximum hydraulics—and the systems don’t fight each other.”

Cromer again mentioned that, in his opinion, the 750T needs either a “fork-level” indicator or a hydraulic detent that would automatically level the forks. And having used the 750T with the trencher, Cromer had specific observations about controls.

“I did think that the brake was bit touchy,” said Cromer. “Why not have two pedals, one for inching and the other for braking? If you hit a bump, the movement can cause you to go past the inching part of the pedal’s travel and apply the brake. But, really, it’s not all that difficult to modulate once you get used to it. But as I said before, the optional hand levers to control the throttle and ground speed would the best solution if you’re going to be running a lot of powered attachments.”

“With the telescopic feature, it has the lift height and reach of a considerably larger machine,” said Jorgensen. “That would be an advantage in some applications. It’s not going to keep up with a two-yard wheel loader all day, but you still have the capability of loading larger trucks. It would just work a little slower with its smaller bucket.”

With that statement, Jorgensen comes close to capturing Wacker Neuson’s 750T design rationale.

“It has the working dimensions of a larger wheel loader when handling buckets and forks,” said Petersen, “but it costs significantly less initially and has lower operating costs. Plus it has the hydraulic capacity to handle serious attachments—such as a 60-inch snow blower, trencher or a 12-inch cold planer—while providing a large and, we think, very comfortable cab.”