SPECIFICATIONS OF
FUil
'Mr·
The
'!OIESEL
11
fuel should
be
a natural distillate
~fr:oleum oil
and
must have certain qualities
in
"brder
to
ignite
and
burn
at
the
proper
rate
and
temperature. Field experience has ·shown
that
the
fuel best suited for this
engine
closely approxi-
mates the following specifications:
Gravity
API
.......................
30 -35
Viscosity
Saybolt
Universal
at
l00° F
...
35 -
40
Flash Point
.......................
150°
F.
Diesel Index
..................
48.5 to 65.5
Cetane
Number
...
;
..............
46 to 60
Pour Point
.........................
0°
F.
Volatil-ity
90%
...............
650°
F.
Max.
End Point
98%
Summer
...................
700°
F.
Max.
Winter
......
,
........
600°
F.
Preferable
Sediment
and
Water
.......
~
.........
Trace
Ash , . . . . . . . . . . . . . . . . . . . . .02 of l % Max.
':,•Geriradson
Corban
.........•
03 of l % Max.
},C~o)phur
..............
; . . .
V2
of l % Max.
satisfactory fuel flow through lines'
and
filters
. celd
weather,
the
pour
point
of
the
fuel must
fie.
at
least 10°
F.
below
the
prevailing atmos-
;fJ:iie
API
;gr'°vity of a fuel varies with
its
specific
gravity. The low
API
fuels
are
desirable because
they have a high specific gravity
and
more
heat
·units
per
gallon. H9wever~ 4
''the higher the
API
gravity, the
better
will
be.
th~ ignition quality of
the fuel.
'The ignition quality of a
fuel
is
expressed as; a •
"cetane
number." The higher
the
cefone number,
the
higher
the
quality of the fuel. The higher
cetane
. .
fuel shortens the ignition
delay
period
to
facilitate
starting
and
improve combustion. The
"DIESEL"
index number, which
is
a close approximation of
the
cetane
number,
is
a field method
to
represent
ignition quality. ·
The distillation
90%
point
and
the
end
point
are
important. High volatility
is
~equired to
enable
complete vaporization of
the
fuel, clean combus-
tion,
and
low residue formation.
The flash point of a fuel has no quality significance,
but
is
importcmt with respect to safety
in
storage
and
handling of the fuel.
It
is
important
that
the fuel
be
within the specified
limits for ash, carbon,
water,
and
sediment con-
tent, etc., to prevent excessive
wear
and
damage
to engine parts.
It
is
also important
that
the fuel has lubricating
properties so
that
the fuel injection pump
and
fuel
nozzles
are
adequately
lubricated. At times
it
may
be
necessary to use fuel with no lubricating prop~
erties.
If
this occasion arises,
add
one
quart
of
SAE
lO engine
oil
to every
10
gallons of fuel.
NOTE:
Distillates should be used only
in
emer:
gencies.
When
the proper fuel
is
again available,
the fuel system must
be
drained
and
cleaned before
the proper fuel
is
added.
CAUTION: The sulphur content
of
"DIESEL"
fuel
should
be
as low as possible. The fuel should not
contain a sulphur content
of
more than
V:z
of
1
%.
Generally speaking, a No. 2
"DIESEL"
fuel pur-
chased from a
reputable
oil
company
will
meet
the
above
specifications.
