and retract clutch lever away from operator allowing
2-31. Operation of Shovel Front End Attachment
digging cable to run out.
a. Perform preventive maintenance checks and
Control slack in digging cable by varying pressure on
services (para 3-6); start engine (para 2-10), and
digging brake pedal.
engage engine clutch (fig. 2-24).
d. Continue raising of backhoe boom and dipper
extension until dipper is over the work area; then return
1-7. When positioning crane-shovel near bank, keep
both clutch levers to neutral; hold digging cable tight
about 11/4 to 11/2 times dipper length between crawlers
with pressure on digging brake pedal; allow backhoe
and edge of bank.
boom and dipper to lower, controlling rate of descent by
pressure on hoist brake pedal.
e. Fill dipper by pulling crowd and retract clutch
pressure on hoist brake pedal.
lever toward operator, at same time keeping tension on
d. To crowd dipper into bank, extend dipper stick
hoist cable by applying pressure on hoist brake pedal.
by pulling crowd and retract clutch lever toward
Note. Depth of backhoe dipper cut is
operator, then returning lever to neutral.
controlled by tension on hoist brake pedal. If hoist
e. To load dipper from bank, move hoist clutch
cable goes slack, dipper will dig in instead of slicing
lever toward operator, then just a moment later, pull
crowd and retract clutch lever toward operator.
material from the cut.
Note.
The dipper should slice a thin layer
f. Stop travel of backhoe dipper before dipper
from bank rather than digging in.
sheave (fig. 2-17) strikes boom, by returning crowd and
retract clutch lever to neutral and applying pressure to
f. When dipper is loaded, move crowd and retract
digging brake pedal.
clutch lever away from operator and retract dipper from
g. Raise dipper out of cut and to dumping height
bank.
by holding pressure on digging brake pedal (keeping
dipper close to boom), and moving hoist clutch and
return hoist clutch to neutral and apply hoist brake
propel brake lever toward operator. When dipper is at
pedal, then swing dipper (para 2-12b) over unloading
proper height return clutch lever to neutral and apply
area. Apply swing brake (fig. 2-23) when dipper is in
pressure to hoist brake pedal.
unloading position, then move dipper trip lever to open
dipper door and dump load.
area.
i. Dump load by moving hoist clutch and propel
then position crane-shovel for digging, and repeat above
brake lever toward operator, at the same time moving
work cycle as necessary.
crowd and retract clutch lever away from operator,
i. When work is finished for the day, lower dipper
keeping pressure on digging brake pedal to prevent
to the ground, and disengage engine clutch (fig. 2-24).
overrunning of digging cable. When load is dumped
and stick is extended return hoist clutch and propel
maintenance checks and services (para 3-6).
brake lever and crowd and retract clutch lever to neutral,
then apply pressure to both brake pedals to hold
2-32. Operation of Backhoe Front End Attachment
backhoe in position.
a. Perform preventive maintenance checks and
services (para 3-6); start engine (para 2-10), and
work area.
engage engine clutch (fig. 2-24).
k. Repeat the above work cycle as necessary.
Note.
Observe that the position of
l. When work is through for the day lower dipper
auxiliary gantry (fig. 2-17) is almost vertical, and the
to the ground, and disengage engine clutch (fig. 2-24).
backstop is almost closed. Adjust position, if
necessary, as described for raising or lowering of
maintenance checks and services (para 3-6).
boom (para 2-12c).
b. Take up slack in hoist cable and digging cable
2-33. Operation
of
Piledriver
Front
End
by moving hoist clutch and propel brake lever and crowd
Attachment
and retract clutch lever (fig. 2-23) toward operator.
a. Perform preventive maintenance checks and
Move clutch levers back to neutral when cable tension is
services (para 3-6); start engine (para 2-10), and
equal.
engage engine clutch (fig. 2-24).
c. To raise backhoe dipper boom and extend
dipper, pull the hoist clutch and propel brake lever (fig.
2-39
