Maintainability Excels with E Series

Sept. 28, 2010

Case unveiled the first in its new E Series wheel loaders at its Tomahawk, Wis., facility in June. Models 721E, 721E/XT and 821E replace their 721D and 821C counterparts with Tier III diesel engines, more material retention, and improvements in operator comfort and serviceability.

Marketing manager David Wolf says Case used Society of Automotive Engineers' maintainability measures to evaluate such variables as change intervals, tools required to do various maintenance operations, and the number of access compartments to be opened. Based on those studies, he says, the loaders offer "best-in-class maintainability."

In focus groups and one-on-one interviews, maintainability came across as a high need. "Service techs are very vocal on their frustrations," Wolf says. "If I can get the service tech in the buying process, he's a great ally." The new loaders have improvements such as three remote drains for coolant and engine and hydraulic oil that are ganged at ground level.

Key to the company's ability to make such maintainability claims is the mid-mount cooling module, which allows the engine to be moved behind the rear axle, opening up the opportunity to slope the loader's hood. The one-piece hood is then electrically actuated to provide easy access to both the engine and the daily maintenance checkpoints. "The only tool required for service checks is a rag to wipe oil off the dipstick," Wolf says. New to the cooling module with the Tier III engine is a fuel cooler, positioned near the firewall.

The 6.7-liter Case diesel (providing 183 and 213 horsepower, respectively) gives the loader three power curves (max, standard and economy) and four work modes (max, standard, economy and auto). In auto mode, the electronically controlled engine adjusts between power curves to move the maximum amount of material per pound of fuel. Overall fuel efficiency has been improved between 5 and 8 percent.

Case teams the new engine with ZF transmission and axles for a "matched power train," Wolf says. "Limited-slip axles on the front and rear transfer power automatically from the wheel that's slipping to the wheel that is gripping," he says.

In addition, Case has moved the planetary and the wet-disc brakes outside the frame for improved serviceability and machine stability. "The emphasis is on serviceability," Wolf says. "It can be done at the wheel end instead of having to drop an axle."

E Series operators will find a larger cab with more creature comforts, including an in-cab cooler box that has a diffuser to run hot/cold air. Access has been improved by angling the step 5 degrees, Wolf says. "We're driving for operator comfort."

Inside, features include a tilt steering column and infinitely adjustable seat, arm rests and control placement. Floor-to-ceiling glass enables the operator to see all around the machine, providing "a clear, direct view to the front tires and to the bucket edge," Wolf says. Cab door and right-hand windows swing back 180 degrees for maximum cross ventilation.

On the loader end, Ride Control keeps operators from bouncing during travel functions. In the lift cylinders, oil goes through an accumulator and the arms then act like a shock absorber, Wolf says. Ride Control can be set for full-time or auto modes. In auto, the system kicks in after 3 mph.

Also on the loader end, Case redesigned the bucket to improve cutting and material retention. The bolt-on cutting edge was extended and thinned, enabling it to push into a pile more efficiently. The bottom floor plate is set at a 5-degree angle to smooth the transition of material from the cutting edge to the back curvature of the bucket. "This creates more rolling of the material to fill the bucket more rapidly," Wolf says.

Retention is further improved by raising the hinge pin, he says. E Series has the pins up out of the dirt, which keeps them cleaner and also provides for more efficient curling and loading.

Case 821E wheel loader
Case 821E allows operators to match power to fuel economy.
Case 821E allows operators to match power to fuel economy. In high-production activities such as aggregates operations, they may choose maximum power at all times for high breakout force and fast cycling.
One-piece flip-up hood, a lift-up panel over the tire, and a removable inner tire fender give the E Series "best-in-class" maintainability, says Case.
Tables:
E Series Specifications
Model Net HP Operating Weight (lb.) Bucket Capacity (cu. yd.)
Source: Case Construction Equipment
The first loaders in Case's E Series compete in the 175–200-hp and 200–225-hp ranges. For more wheel-loader specifications, and 71 other types of machines, visit ConstructionEquipment.com.
721E 183 30,644 3.01
721E/XT 183 31,574 3.00
821E 213 37,844 3.78