Specifications

300 SERIES MAN HOLE DIGGER
FORM GOM12070702, VERSION 1.2
25
OPERATING THE HOLE DIGGER.
Application: All 300 Series models.
1) Do not attempt to begin digging with the Hole Digger
until both the Crew Chief and Crew Member have
acknowledged to each other that they are ready and
are in full control of the machine.
2) The Crew Chief rotates the throttle control
counterclockwise to increase the engine speed. The
auger will begin to rotate when the engine speed
reaches the centrifugal clutch initial engagement
speed.
3) Normal operating procedure for the Hole Digger is to
dig with the engine operating at full, governed speed to
allow the centrifugal clutch to become more firmly
engaged. This procedure will transmit more usable
power to the auger, resulting in greater productivity and
less component wear.
When digging in areas filled with known,
buried obstructions such as tree roots,
rocks and other debris, operate the Hole
Dig g er at le s s th an ful l , go v er ne d (a n
intermediate) speed to insure a more rapid
release of the centrifugal clutch when an
obs t ru ct io n is enc o un te re d. This is an
industry wide operating procedure.
4) The Hole Digger is equipped with a centrifugal clutch
assembly within the transmission. Newton's Law of
Physics allow the centrifugal clutch assembly to
ALWAYS slip (NOT DISENGAGE) whenever
overloaded or if the auger comes in contact with a
buried obstruction. The term slippage is not intended to
infer that the centrifugal clutch assembly becomes fully
disengaged with no horsepower and torque being
transmitted to the auger. In the slipping mode, a
centrifugal clutch still transmits a specific amount of
horsepower and torque to the auger. This specific
amount of horsepower and torque is directly
proportional to many factors including: the mechanical
condition of the centrifugal clutch assembly and the
rotational speed of the centrifugal clutch assembly
when the initial slippage occurs. The response time for
the centrifugal clutch assembly to react to an overload
condition is directly proportional to its rotational speed.
The higher the rotational speed (RPM) of the
centrifugal clutch at the time of overload, the greater
amount of time it requires to react and actually slip.
This phenomenon is inherent with all centrifugal clutch
assemblies. It is inherent with all powered equipment
incorporating such a device.
STRIKING BURIED OBSTRUCTIONS SUCH AS
TREE ROOTS, ROCKS AND OTHER DEBRIS AT
ANY SPECIFIC ENGINE OPERATING SPEED CAN
CAUSE THE HOLE DIGGER TO TRANSMIT
REACTIONAR
Y TYPE "IMPACT" LOADS TO THE
OPERATORS. THESE TYPES OF LOADS ARE
CHARACTERIZED BY A SHARP, PULSATING
MOVEMENT OF THE HOLE DIGGER IN A
COUNTERCLOCKWISE DIRECTION (AS VIEWED
BY THE OPERATOR). SUCH LOADS CAN LEAD TO
THE LOSS OF OPERATOR CONTROL AND RESULT
IN PERSONAL INJURY. THE OPERATIONAL
EFFECTS ARE ALIKE TO THAT OF UTILIZING A
COMMON ELECTRIC DRILL AND OTHER,
ROTATION TYPE, POWERED EQUIPMENT. THE
RELA
TED PHENOMENON IS INHERENT WITH ALL
SUCH TYPES OF ROTATION TYPE, POWERED
EQUIPMENT AND IS TERMED AS KICKBACK.
UNDERSTANDING KICKBACK.
Application: All 300 Series models.
The operation of the Hole Digger involves engine
torque being transmitted and multiplied by the
transmission to the auger. The energy is then used to
dig holes. But to every force (action), there is always a
reaction force in the opposite direction. Thus, if the
auger
contacts a buried obstruction, the operators will
feel the left side handles of the Hole Digger being
"thrusted" towards them. This "thrusting" force
experienced by the operators is called kickback. The
speed (and magnitude of the resulting impact force) at
which the auger strikes the buried object is directly
proportional to the amount/speed of the kickback force
experienced by the operators. The torque and kickback
generated by the digging process is inherent with a
portable, two man Hole Digger and can not be
eliminated by any operation and/or design
characteristic. The operational effects are alike to that
of utilizing a common, electric drill and other, rotation
type, powered tools.
BACK CARE/PROPER LIFTING INFORMATION
Application: All 300 Series models.
In addition to kickback forces encountered during the