Caterpillar: E Series meets new emissions regs

The five new compact-radius Cat E Series Mini Hydraulic Excavators — 303.5E CR, 304E CR, 305E CR, 305.5E CR and 308E CR SB — all use new engines that meet Stage IIIB /Tier 4 Interim emissions regulations and incorporate new features such as the Complete Operation, Maintenance, Performance, And Security System (COMPASS) control panel, standard high-ambient cooling package, more efficient auxiliary hydraulics, and redesigned control layout. Built into the COMPASS monitor are an anti-theft system, which requires a five-digit alphanumeric password to start the machine, and an Economy Mode feature (3.5- to 5.5-ton machines), which Cat says can potentially lower fuel use up to 20 percent by adjusting engine speed. An automatic engine-idle system drops engine rpm to idle after four seconds of inactivity.

A continuous-flow feature for auxiliary hydraulics, which maintains selected flow without operator intervention, is also available through COMPASS.

Additional refinements for the five E Series models include a standard high-ambient cooling package, electronic fuel-pump-priming system, a four-post canopy (3.5- to 5.5-ton machines), new ergonomic joysticks, and relocation of a number of controls such as the two-speed travel switch to the blade lever, secondary auxiliary hydraulic engagement to the left joystick, and manual pattern changer from the floor to the COMPASS monitor.

All new E Series machines use an end-damping system in both the boom and stick cylinders to reduce shock loads and to reduce material spillage. E Series sticks are thumb-ready, with brackets welded in place and relief valves already built into the main valve. The 308E CR SB will be available only in a swing boom configuration.