August 5, 2011
Caterpillar says its new 390D L hydraulic excavator has a refined design that provides greater hydraulic power, stronger structural components, added safety and convenience features, and improved serviceability. The 198,570 pound-excavator’s Tier III-compliant, C18 Acert diesel engine boasts advanced electronic control, precise fuel delivery, and refined air management. The 5,080-horsepower engine is said to allow full power at maximum revolutions per minute for efficient hydraulic pump operation and positive hydraulic response.
Design enhancements in the implement’s hydraulic system allow greater digging and lifting forces than its 385C predecessor. The company says an increase in operating pressure, combined with larger diameter hydraulic cylinders, results in a 9-percent boost in digging arm and bucket breakout forces. Over-the-end lifting capacity is increased by 9 percent, and over-the-side capacity is up nearly 20 percent. The undercarriage features redesigned links that operate with lower stress, forged idlers for durability, and heavy-duty track rollers and carrier rollers. Service improvements include an electric fuel-priming pump, a dual-element air cleaner, filters that are accessible from the left side of the machine, easy-to-change spin-on filters, 20-inch-wide walkways, and an electronic warning system that alerts the operator if the air filter or hydraulic filter is approaching restriction limits.