i. When work is finished for the day, lower dipper
to ground, and disengage engine clutch (fig. 2-24).
f. Stop travel of backhoe dipper before dipper
sheave (fig. 2-17) strikes boom, by returning crowd and
retract clutch lever to neutral and applying pressure to
maintenance checks and services (para 3-6).
digging brake pedal.
g. Raise dipper out of cut and to dumping height
2-32. Operation of Backhoe Front End Attachment.
by holding pressure on digging brake pedal (keeping
a. Perform preventive maintenance checks and
dipper close to boom), and moving hoist clutch and
services (para 3-6); start engine (para 2-10), and
propel brake lever toward operator. When dipper is at
engage engine clutch (fig. 2-24).
proper height return clutch lever to neutral and apply
Note
pressure to hoist brake pedal.
Observe that the position of auxiliary
gantry (fig. 2-17) is almost vertical,
area.
and the backstop is almost closed.
i. Dump load by moving hoist clutch and propel
Adjust position, if necessary, as
brake lever toward operator, at the same time moving
described for raising or lowering of
crowd and retract clutch lever away from operator,
boom (para 2-12c).
keeping pressure on digging brake pedal to prevent
overrunning of digging cable. When load is dumped
b. Take up slack in hoist cable and digging cable
and stick is extended return hoist clutch and propel
by moving hoist clutch and propel brake lever and crowd
brake lever and crowd and retract clutch lever to neutral,
and retract clutch lever (fig. 2-23) toward operator.
then apply pressure to both brake pedals to hold
Move clutch levers back to neutral when cable tension is
backhoe in position.
equal.
c. To raise backhoe dipper boom and extend
work area.
dipper, pull the hoist clutch and propel brake lever (fig.
k. Repeat the above work cycle as necessary.
l. When work is through for the day lower dipper
and retract clutch lever away from operator allowing
to the ground, and disengage engine clutch (fig. 2-24).
digging cable to run out. Control slack in digging cable
by varying pressure on digging brake pedal.
maintenance checks and services (para 3-6)
d. Continue raising of backhoe boom and dipper
extension until dipper is over the work area; then return
both clutch levers to neutral; hold digging cable tight
2-33. Operation of Piledriver Front End Attachment
with pressure on digging brake pedal; allow backhoe
boom and dipper to lower, controlling rate of descent by
a. Perform preventive maintenance checks and
pressure on hoist brake pedal.
services (para 34;); start engine (para 2-10), and engage
e. Fill dipper by pulling crowd and retract clutch
engine clutch (fig. 2-24).
lever toward operator, at same time keeping tension on
hoist cable by applying pressure on hoist brake pedal.
hammer, then lift hammer and pile follower by moving
Note
hoist clutch lever toward operator. When hammer
Depth of backhoe dipper cut is
reaches top of hammer guides, return hoist clutch lever
controlled by tension on hoist brake
to neutral, apply hoist brake pedal, and set hoist brake
pedal. If hoist cable goes slack,
lock (fig. 2-23) to hold hammer in raised position.
dipper will dig in instead of slicing
c. Run pile handling cable off drum by moving
material from the cut. The pitch
crowd and retract clutch lever away from operator, and
brace between dipper and stick is
at same time applying pressure to digging brake pedal
adjustable to three positions. For
to prevent pile cable from overrunning. Attach pile
normal operation brace pin is usually
handling cable to upper end of a pile and raise it into
set in center hole. For very deep
position within pile leads by moving crowd and retract
excavation, set brace pin in lower
clutch lever toward operator, return clutch to neutral and
hole. Where maximum height of lift
apply digging brake when pile is within pile leads.
is required for dumping, set brace
d. Position pile in desired location by moving crane
pin in upper hole.
lower point of pile to ground by slowly moving crowd and
retract lever away
2-37
