Fuel Contamination
Generally, fuel contamination occurs
as the result of improper fuel han-
dling. The most common types of
contamination are water, dirt, and
microbial growth (“black slime”). The
formation of varnishes and gums
resulting from poor stability or
extended storage (“stale fuel”) also
affects fuel quality. The best treat-
ment for contamination is prevention
by maintaining a clean storage sys-
tem and choosing a reputable fuel
supplier.
Fuel Additives
Detroit Diesel engines are designed
to operate satisfactorily on a wide
range of diesel fuels. Some fuels may
be marketed which contain perfor-
mance additives and are identified
as premium diesel fuel. Detroit Diesel
engines do not require the use of
such fuels; however, they may be
used at the customer's discretion.
Aftermarket Supplemental Fuel
Additives—
There are many aftermar-
ket products available today which are
intended to be added to the fuel by the
customer. These include a variety of
independently marketed products
which claim to be:
—Cetane Improvers
—Emission Control Additives
—Detergents
—Combustion Improvers
—Smoke Suppressants
—Cold Weather Flow Improvers
Supplemental additives are not
recommended due to potential
injector system or engine damage.
Our experience has been that such
additives increase operating costs
without providing benefit.
51
used, but they may result in reduced
engine power and/or fuel mileage.
Fuel Cleanliness
Fuel should be clean and free of con-
tamination. Storage tanks and stored
fuel 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. If fuel is stored on site,
the following is recommended:
1. Do not use galvanized steel or
sheet metal tanks and galvanized
pipes or fittings in any diesel fuel
storage, delivery, or fuel system.
The fuel oil will react chemically
with the zinc coating, forming a
compound which can clog filters
and cause engine damage.
2. Keep the storage tank filler cap
covered to prevent contamination
by rain water.
3. Keep the tank clean especially
around the filler cap and tap
areas.
4. Position the tank so that it is tilted
slightly toward the bottom drain.
This will make draining of accu-
mulated water and sediment a lit-
tle easier.
5. Minimize condensation by keeping
the tank reasonably filled at all
times.
6. After filling the fuel storage tank,
wait a few hours before filling
equipment tanks to allow contami-
nants to settle.
Fuel Sulfur Content
The sulfur content of the fuel should
be as low as possible to avoid pre-
mature wear of piston rings and lin-
ers, avoid excessive deposit
formation, and minimize sulfur diox-
ide exhausted into the atmosphere.
Limited amounts of sulfur can be tol-
erated, but the amount in the fuel
and engine operating conditions can
influence corrosion and deposit for-
mation tendencies.
The use of fuel
containing greater than 0.5 mass
percent sulfur will require more
frequent oil changes.
All 1994 model year on-highway
diesel engines manufactured for use
in the United States must meet a new
reduced exhaust particulate content
of 0.10 gram/horsepower-hour. To
meet this requirement, all diesel fuel
sold in the United States for
on-high-
way use
will be limited to 0.05%
maximum sulfur content. The sulfur
content of diesel fuel for
off-highway
use
will continue to be specified at
0.5% maximum. Off-highway fuel will
be dyed blue for identification.
NOTE:
The use of low sulfur diesel
fuel does not permit extension of
engine lube oil drain and filter
change intervals.
Cold Weather Operation
In cold weather, diesel fuel will form
wax crystals which can restrict flow
and clog filters. Fuel oil suppliers
approach this problem several ways.
Some provide a specially refined
product, while others may use flow-
improving additives or winter blends.
Winter blended fuel will likely contain
kerosene or 1-D fuel, which provide
good cloud point temperatures, but
result in a lighter fuel with a lower
heat content. These fuels may be
50
6. Add oil as required to bring the
level to the “full” mark on the dip-
stick.
7. Start and run the engine for a short
period and check for leaks. After
any leaks have been corrected,
stop the engine long enough for
oil from various parts of the
engine to drain back to the
crankcase (approximately 20 min-
utes). Add oil as required to bring
the level to the proper mark on the
dipstick.
D. How to Select Fuel Oil
Quality
Fuel quality is an important factor in
obtaining satisfactory engine perfor-
mance, long engine life, and accept-
able exhaust emission levels. Detroit
Diesel engines are designed to oper-
ate on most diesel fuels marketed
today.
In general, fuels meeting the prop-
erties of ASTM designation D 975
(grades 1-D and 2-D) have provided
satisfactory performance.
The fuels used must be clean, com-
pletely distilled, stable, and non-corro-
sive. For more information regarding
the significance of these properties
and selection of the proper fuel, refer
to publication “Engine Requirements—
Lubricating Oil, Fuel, and Filters”
(7SE270), available from authorized
Detroit Diesel service outlets
NOTICE:
If the oil level is constantly above
normal and excess lube oil has not
been added to the crankcase, con-
sult with an authorized Detroit Diesel
service outlet for the cause. Fuel or
coolant dilution of lube oil can result
in serious engine damage.
Summary of Contents for 92 Series
Page 41: ...NOTES 77 NOTES 76 ...
Page 42: ...NOTES 78 ...