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Verified Technologies for SmartWay and Clean Diesel

Caterpillar Technology—Marine Engine Emissions Upgrade Group Kit #2 (MUI to Tier 1)

This retrofit technology is included on EPA's Verified Technologies List for Clean Diesel.

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Technology specifications

Engine Model/Application

Caterpillar 3508, 3512, and 3516 (large cam bore) diesel engines for non-road marine applications, model year 1994 – 2006

Retrofit Fuel, Max Sulfur 15 parts per million (ppm)
Reduction in particulate matter (PM) 45%
Reduction in nitrogen oxide (NOx) 10.05g/kW-hr (Marine Diesel EngineTier 1 Level  a)
Reduction in hydrocarbons (HC) 28%
Reduction in carbon monoxide (CO) 65%
Reduction in carbon dioxide (CO2)b 3%

a The Tier 1 standard is a range based on engine speed, with higher limits for slower engines. Formula is 45×(rpm)-0.2. The Diesel Emissions Quantifier (DEQ) may be used to estimate reductions from Tier 0 (or unregulated) to Tier 1 levels.

b The CO2 level of reduction is based on a laboratory E3 general marine engine test cycle; the level of reduction may vary under different conditions.

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Criteria to achieve emission reductions

This technology is approved for Caterpillar 3500 Series MUI marine variable speed propulsion engines with rated power greater than 600 horsepower originally manufactured between 1994 and 2006 model years. Please note that the level of reduction is based on the ISO 8178 E3 general marine duty cycle. The following criteria must be met in order for appropriately retrofitted engines to achieve the aforementioned emission reductions:

  1. The Caterpillar 3500 Marine Engine EUG Kit #2 includes components necessary to upgrade Caterpillar model 3508, 3512, and 3516 diesel engines with model years 1994 through 2006 from MUI to Tier 1 emission levels. The primary critical components are the electronic control module, cylinder packs, oil cooler, turbocharger, fuel injectors, and after-coolers if applicable.
  2. The servicing dealer must follow specific installation instructions approved by Caterpillar and validate that the upgraded engine has the necessary EUI components installed and has been tested to ensure the proper fuel delivery, power, torque and speed. The dealer must submit a validation form to Caterpillar in order to receive a label for the upgraded engine.
  3. The engine must be operated on ultra-low sulfur diesel fuel (ULSD) of 15 ppm or less.
  4. This verification is for engines used in vessels with variable speed propulsion systems and is not applicable for engines used in recreational or constant speed propulsion applications.

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Verification Letter from EPA

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