Fuel, Oil and Coolant Specifications
DETROIT DIESEL FUEL OIL SPECIFICATIONS
GENERAL CONSIDERATIONS
The quality of fuel oil used for high-speed diesel engine operation is a very important factor in obtaining
satisfactory engine performance, long engine life, and acceptable exhaust.
Fuel selected should be completely distilled material. That is, the -fuel should show at least 98 percent by volume
recovery when subjected to ASTM D-86 distillation. Fuels marketed to meet Federal Specification VV-F-800 (grades DF-
1 and DF-2) and ASTM Designation D-975 (grades 1-D and 2-D) meet the completely distilled criteria. Some of the
general properties of VV-F-800 and ASTM D-975 fuels are shown below.
FEDERAL SPECIFICATION & ASTM DIESEL FUEL PROPERTIES
Residual fuels and domestic furnace oils are not considered
satisfactory for Detroit Diesel engines: however, some may be
acceptable.
(See "DETROIT DIESEL FUEL OIL
SPECIFICATIONS.")
NOTE: Detroit Diesel Allison does not
recommend the use of drained lubricating oil
as a diesel fuel oil. Furthermore, Detroit
Diesel will not be responsible for any engine
detrimental effects which it determines
resulted from this practice.
All diesel fuel oil contains a certain amount of sulfur. Too high
a sulfur content results in excessive cylinder wear due to acid
build-up in the lubricating oil. For most satisfactory engine
life, fuels containing less than 0.5% sulfur should be used.
Fuel oil should be clean and free of contamination. Storage tanks should be inspected regularly for dirt, water or water-
emulsion sludge, and cleaned if contaminated. Storage instability of the fuel can lead to the formation of varnish or
sludge in the tank. The presence of these contaminants from storage instability must be resolved with the fuel supplier.
DETROIT DIESEL FUEL OIL SPECIFICATIONS
Detroit Diesel Allison designs, develops, and manufactures commercial diesel engines to operate on diesel fuels
classified by the ASTM as Designation D-975 (grades I-D and 2-D). These grades are very similar to grades DF-I and
DF-2 of Federal Specification VV-F-800. Residual fuels and furnace oils, generally, are not considered satisfactory for
Detroit Diesel engines. In some regions, however, fuel suppliers may distribute one fuel that is marketed as either diesel
fuel (ASTM D-975) or domestic heating fuel (ASTM D-396) sometimes identified as furnace oil. In this case, the fuel
should be investigated to determine whether the properties conform with those shown in the "FUEL OIL SELECTION
CHART" presented in this specification.
The "FUEL OIL SELECTION CHART" also will serve as a guide in the selection of the proper fuel for various
applications. The fuels used must be clean, completely distilled, stable, and non-corrosive, DISTILLATION RANGE,
CETANE NUMBER, and SULFUR CONTENT are three of the most important properties of diesel fuels that must be
controlled to insure optimum combustion and minimum wear.
Engine speed, load, and ambient temperature influence the selection of fuels with respect to distillation range and cetane
number. The sulfur content of the fuel must be as low as possible to avoid excessive deposit formation, premature wear,
and to minimize the sulfur dioxide exhausted into the atmosphere.
To assure that the fuel you use meets the required properties, enlist the aid of a reputable fuel oil supplier.
The responsibility for clean fuel lies with the fuel supplier as well as the operator. During cold weather engine operation,
the cloud point (the temperature at which wax crystals begin to form in diesel fuel) should be 10F (6C) below the lowest
expected fuel temperature to prevent clogging of the fuel filters by wax crystals.
At temperatures below -20F (-29C), consult an authorized Detroit Diesel Allison service outlet, since particular
attention must be given to the cooling system, lubricating system, fuel system, electrical system, and cold weather
starting aids for efficient engine starting and operation.
FUEL OIL SELECTION CHART
NOTE: When prolonged idling periods or
cold weather conditions below 32F (0C)
are encountered. the use of lighter distillate
fuels may be more practical. The same
consideration must be made when operating
at altitudes above 5,000 ft.
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