The new series of Hitachi Zaxis Dash-5 excavators feature Isuzu engines with cooled exhaust gas recirculation (EGR) and exhaust filters consisting of a diesel oxidation catalyst/diesel particulate filter to meet the 2011 EPA Interim Tier IV (IT4)/EU Stage IIIB emissions regulations mandated for 174- to 750-hp (129 to 559 kW) diesel engines.
“Hitachi believes this is the simplest IT4 solution,” said Mark Wall, product marketing manager of Hitachi construction excavators in the Americas. “And it continues to deliver the productivity, fuel efficiency and reliability customers expect from Hitachi.”
Hitachi’s approach to meeting IT4 regulations is an evolution of the clean-burning and fuel-efficient Tier III/Stage IIIA Isuzu engine platform used in Hitachi Dash-3 excavators.
The Isuzu cooled EGR engine platform for IT4 compliance is less complex to maintain compared to SCR (selective catalytic reduction) systems.
“Unlike SCR, this IT4 solution doesn’t require liquid urea to achieve the necessary emissions reduction. There aren’t any other fluids to acquire, fill and store on job sites,” Wall said. “EGR requires just one fluid — diesel fuel.”
“Hitachi dealers are ready to service and support these new engines and optimize the overall efficiency of the excavator,” Wall said.