TM 5-3820-245-14&P
5-3. FEED RAM ASSEMBLY TROUBLE SHOOTING (Continued)
CONDITION
PROBABLE CAUSE
REMEDY
Packing nut
Lower packing worn out. NEW
Remove lower packing nut and
completely
PACKING SOAK IN HYD
gland. Using hydraulic
taken up.
OIL 4 to 8 HRS. BEFORE
pressure blow out old packing,
INSTALLING.
Replace with new set of pack-
ing allowing a slight amount
of seepage.
Excessive leaking
Upper packing nut
Tighten upper packing nut
around main drive
loose.
until slight seepage remains.
on upper portion
of final drive
assembly.
Upper packing nut
Upper packing nut
Loosen upper packing nut
running extremely
too tight.
until slight seepage is
hot.
encountered on the main drive.
Unable to seal flow
Upper packing worn out.
Remove upper packing nut,
of hydraulic oil on
NOT NECESSARY TO
gland and using hydraulic
upper packing drive
SOAK UPPER PACKING.
pressure, blow out old pack-
or packing nut
ing. Replace with a new set
completely taken
of packing, allowing a slight
up.
amount of seepage.
Loss of hydraulic
Piston assembly
Piston rings badly worn or
pressure when
failure.
damaged. A quick method of
retracting kelly
checking is with the feed ram
bar with a loaded
assembly in vertical position.
auger or unable to
Apply down pressure on kelly
keep down pressure
bar until truck is slightly
when digging.
raised off the ground. If
digger falls back at a rapid
pace, disassemble feed ram
assembly and replace piston
rings. If the piston assembly
has deep scars on the piston,
the feed ram cylinder itself
should be checked for damage.
If marks are not excessive,
cylinder can be honed and
reused. If honing does not
dress marks out of cylinder,
replace complete cylinder.
When reassembling, do not
over torque bolts on feed ram
assembly.
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