ISBe/ISB Series Engines – 018-002   Fuel Recommendations and Specifications

Fuel Recommendations

WARNING  Do not mix gasoline, alcohol, or gasohol with diesel fuel. This mixture can cause an explosion.

CAUTION  Due to the precise tolerances of diesel injection systems, it is extremely important that the fuel be kept clean and free of dirt and water. Dirt or water in the system can cause severe damage to both the fuel pump and the fuel injectors.

CAUTION  Lighter fuels can reduce fuel economy or possibly damage the fuel injection pump.

Cummins Inc. recommends the use of ASTM number 2D fuel. The use of number 2D diesel fuel will result in optimum engine performance.

At operating temperatures below 0°C [32°F], acceptable performance can be obtained by using blends of number 2D and number 1D.

NOTE: Engines equipped with diesel particulate filters require the use of diesel fuel with 15 ppm sulfur maximum. There are no acceptable substitutes.

The following chart lists acceptable alternative fuels.

1. Any adjustment to compensate for reduced performance with a fuel system using alternate fuel is
   not warrantable.
2. Winter blend fuels, such as found at commercial fuel dispensing outlets, are combinations of number 1D and number 2D diesel fuel and are acceptable.
3. BTU Content/Degree API Gravity – Low API gravity fuels have a higher thermal energy content (BTU). As a general rule of thumb there is a 3 to 5 percent decrease in BTU content for every 10 degree increase in API gravity, there is also a 0.7 degree API gravity increase with an increase in fuel temperature. This decrease in energy content equates roughly to the same percentage of power loss. Use of fuels with higher API gravity will cause higher than normal fuel consumption.

NOTE: Cummins Inc. recommends that the cetane number of diesel fuel be a minimum of 45 for engines that are expected to operate at temperatures below 0°C [32°F] and a minimum of 40 for engines that are operated at temperatures above 0°C [32°F].

NOTE: Using diesel fuel with lower than recommended cetane number can cause hard starting, instability, and excessive white smoke. To maintain satisfactory operation at low ambient temperatures, it is important to specify diesel fuel of the correct cetane number.

NOTE: Cummins Inc. requires all permissible fuels to have adequate fuel lubricity. This means the BOCLE number is 3100 or greater as measured with the U.S. Army scuffing BOCLE test. The limits for acceptable lubricity are specified as a wear scar diameter less than or equal to 400 micrometers using the high-frequency reciprocating rig test method.

Additional information for fuel recommendations and specifications can be found in Fuel for Cummins® Engines, Bulletin
3379001.