The 95-litre 16-cylinder engine uses a Cummins selective catalytic reduction (SCR) after-treatment to meet the new Tier 4 emission standards which come into force in January 2015. The SD90 locomotive will be re-designated CECX 1919 and will have an output of 3132kW. The locomotive will be owned by Cummins, but will be operated by Indiana Rail Road Company as the lead locomotive hauling 100-wagon trains with a total weight of around 12,700 tonnes. The locomotive is expected to enter service in mid-2014.


The locomotive will be fitted with GPS location and telemetry to enable Cummins to monitor the unit remotely. Field test engineers will be able to fine-tune the engine remotely to improve its fuel efficiency or power output.

The SCR exhaust after-treatment is designed to remove NOx emissions, while the engine combustion removes particulate matter. Cummins says this avoids the need for added complexity on the engine, and enables the combustion formula to be fully optimised for fuel efficiency. The SCR system is designed to occupy a space similar to that of the exhaust silencers.

"The repowered locomotive will demonstrate how well the clean combustion of the QSK95 engine and Cummins SCR exhaust after-treatment work together as an integrated system to achieve the ultra-low Tier 4 emissions levels, easily accommodating the space claim of the larger medium-speed engine it replaces, and requiring no additional cooling capacity," says Mr Randy Nelson, marketing director with Cummins' Rail Business.