ECO News

Regulatory Background For Marine Diesel The following background is provided by Dieselnet: Engine Categories. For the purpose of emission regulations, marine engines are divided into three categories based on displacement (swept volume) per cylinder, as shown in Table 1. Each of the categories represents a different engine technology. Categories 1 and 2 are further dividedContinued

EPA has determined that gasoline marine engines are one of the largest average contributors of HC emissions. Of all categories of nonroad engines, recreational marine engines contribute the second highest average level of HC exhaust emissions. Only small gasoline engines used in lawn and garden equipment emit higher levels on average. The following engines areContinued

In order to comply with the requirements, engine manufacturers must follow strict testing procedures to demonstrate or certify that their engine or vehicle meets the engine emissions standards while operating in a specific service class (test cycle and weight restriction). An engine cannot be placed in a vehicle and operated outside its service class designation.Continued

Heavy-duty vehicles are defined as vehicles of GVWR (gross vehicle weight rating) of above 8,500 lbs in the federal jurisdiction and above 14,000 lbs in California (model year 1995 and later). Diesel engines used in heavy-duty vehicles are further divided into service classes by GVWR, as follows. Light heavy-duty diesel engines: 8,500 < LHDDE <Continued