TM 5-4320-218-15
Figure 7. Performance of pump unit pumping gasoline @ 0.75 specific gravity.
is most desirable that the engine speed be held
d. As will be seen from the curves, when liq-
at a constant level. This may be accomplished
uid of a higher specific gravity is pumped, the
simply by adjusting the engine governor control
engine load increases, and care must be ex-
as follows :
ercised that the maximum continuous brake
horsepower is not exceeded. This is accomplish-
The governor lever is furnished with 12 holes
ed by throttling or reduction of the governor
as shown in figure 13 for attaching the gover-
setting as necessary.
nor spring. It is very important that the spring
e. During pump operation with the specific
is hooked into the proper hole to suit the speed
gravity of the fuel being pumped known,
at which the engine is operated. The table
the fuel being pumped in gallons per
shows the full load and no load speeds of the
minute may be reasonably accurately ob-
engine and the hole corresponding thereto. The
tained; the engine speed and the pump dis-
full load speed will be from 150 to 125 revolu-
charge pressures are noted and fuel flow read
tions less than the load speed. As an example,
directly from the curve of pump perform-
if the engine is to be operated at 2000 rpm with
ance. Further, the engine horsepower may be
load, the spring should be hooked into the
determined at the same time.
eighth hole in the governor lever and the spring
tension adjusted by means of the adjusting
f. For various operations of the pump
screw on the spring to run at 2125 rpm no load
unit, i.e., transfer, dispensing, and receiving it
or approximately 2000 rpm under load.
