TM 5-3805-281-24-1
Operational Checkout Procedure
YES: Go to next check.
SWING DYNAMIC
CAUTION: Make sure area is clear and large
BRAKE CHECK
enough to swing extended arm and bucket.
NO: Check swing motor
Machine must be on level ground.
leakage. Check swing
motor crossover relief
Position upperstructure with boom in front.
valve. Go to Group
9005
9025-25. Check swing
10
Put arm and bucket in fully extended position with bucket
valve spool. Go to Group
15
900 mm (3 ft) above ground level.
3360.
T6479AY UN19OCT88
Operate engine at fast idle.
Actuate swing control valve to full stroke. Swing around
90 degrees and release lever.
Does upperstructure stop within 45 degrees (1/8 turn)
after releasing lever?
Repeat procedure in opposite direction.
1/1
SWING CIRCUIT
Run engine at slow idle.
YES: Go to next check.
LEAKAGE CHECK
Position machine on a side hill or raise one side of
NO: Check swing circuit
machine 300 mm (1 ft) with the boom and put blocks
leakage. Go to Group
under track.
9025-25.
Position bucket 300 mm (1 ft) off the ground at
maximum reach.
T6479AZ UN19OCT88
Actuate bucket curl function over relief.
NOTE: Actuating the bucket function releases the
mechanical swing park brake.
Does upperstructure move only slightly?
1/1
DIG FUNCTION DRIFT
Run engine at slow idle.
YES: Check cylinder drift.
CHECK
Go to 9025-25. Inspect
reduced leakage valves
Fill bucket with dirt. Position bucket at maximum reach
for boom down and arm
with bucket 2 in. (50 mm) above ground.
in functions. Go to Group
3360.
Observe bucket for 1 minute.
NO: Go to next check.
Does bucket drift down to ground within 1 minute?
T6290AF UN19OCT88
1/1
2-15