Fuels may be polluted by dirt, rust, water, or by
includes refilling fuels, lubricants, coolants, hydraulic
accidentally combining with other types of petroleum
fluids, and other consumables (frequently used
products. If the products are to serve the purposes for
materials).
which they are intended, it is vital that you avoid such
You should be able to identify the types of fuels and
pollution. Dirt and water in fuels are primary causes of
lubricants, their specific use, and the method and
premature engine failure. When you handle fuels,
frequency of application. Proper selection of fuels is
cleanliness is essential.
also important. You do not put diesel fuel in a gasoline
engine or gasoline in a diesel engine. Yet, it frequently
GASOLINE.--Gasoline contains carbon and
happens.
hydrogen in proportions that allow it to burn freely and
produce heat energy. It evaporates (changes to a vapor)
Perhaps you have seen what happens to the wheel
at any temperature. Because gasoline vapors are
bearings in an automobile when they were not properly
heavier than air, they sink to the ground (fig. 1-2). To
lubricated. In some cases the bearings were damaged
decrease the fire hazard of having the gasoline vapors in
due to lack of grease or by use of the wrong type of
a closed place where instant combustion could take
grease. This type of damage can be avoided if the wheel
place, the place in which gasoline is used SHOULD BE
bearings are inspected at regular intervals and if the
THOROUGHLY VENTILATED THROUGH OPEN-
correct lubricant is selected. Servicing modern support
INGS NEAR THE FLOOR.
equipment is important. A good knowledge of correct
fuels and lubricants makes the job easier and safer for
If all the potential heat energy contained in a gallon
the equipment.
of gasoline could be turned into actual work, a motor
vehicle could run many more miles on each gallon.
SERVICING PROCEDURES
However, only a small percentage of this heat energy is
turned into power by the engine. Most authorities
Usually, servicing support equipment is not very
consider the power losses within the engine to be as
complicated, but it is extremely important. You should
follows:
be able to determine how and why servicing can often
be so critical. For example, one item of equipment may
PERCENT OF
require several different types of oil, grease, or fluids.
ENGINE
POWER LOSS
Selection of the correct types and proper application to
Cooling system
35
the proper points can make the difference between a
Exhaust gases
35
piece of equipment that gives excellent performance
Engine friction
5 to 10
and one that is damaged beyond repair.
Total
75 to 80
Complete servicing details can be found in the
operation, servicing, and repair instructions section in
the MIM written for that particular type and model of
equipment. Servicing information can also be found in
the MRCs (maintenance requirements cards).
CONSUMABLES
GAS
The following text discusses some of the fuels,
lubricants, hydraulic fluids, and coolants used in
support equipment.
Fuels
Fuels for gasoline and diesel engines are
by-products of petroleum. Petroleum products include
gasoline, kerosene, diesel fuel, lubricating oils, gear
lubricants, and greases. Many different products are
added to the raw by-products to obtain a fuel that can
AS1f0102
perform well in modern equipment.
Figure 1-2.--Silhouette of gas vapors falling. Caution:
Gasoline vapors are heavier than air.
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