DR Power Backhoe 2008 - Manual (Page 40)

36 DR ®
DIRT BOSS™ TOWABLE BACKHOE
Troubleshooting Table (continued)
S YMPTOM P OSSIBLE C AUSE
Hydraulic Fluid
Heating. ⇒ Dirty hydraulic fluid; Drain fluid and refill.
⇒ Control valve handle held open too long; Return control valve handle
to neutral position when not in use.
⇒ Hydraulic fluid too light in hot weather; Use recommended fluid.
⇒ Engine running too fast; Reduce throttle.
⇒ Damaged hydraulic lines; Replace damaged lines.
External leakage. ⇒ Damaged O-rings on valve spools; Repair control valve.
⇒ Cylinder seals damaged; Repair cylinder.
⇒ Broken hydraulic line; Check for leaks and replace line.
Swing cylinder
malfunctioning.
⇒ Hydraulic fluid leaking past packing or seals; Replace packing or seals.
⇒ Faulty cross-over relief valve; Clean or replace.
Control valve sticking
or working hard. ⇒ Scored bore or bent spool; Repair or replace worn valve.
⇒
Control linkage misaligned; Correct misalignment.
⇒
Return spring binding or broken; Replace spring.
⇒
Foreign matter in spool bore; Clean valve.
⇒
Dirty hydraulic fluid; Drain fluid and refill.
Spongy or jerking
action of cylinders
and/or very noisy
pump action. ⇒ Low hydraulic fluid supply; Add fluid.
⇒ Cold hydraulic fluid too stiff; Use recommended fluid.
⇒ Air in system; Purge system of air by operating machine at maximum
hydraulic fluid flow and through full movements.
⇒ Pinched suction line to pump; Replace hose, rout to prevent kinking or
pinching.
CENTER THE BOOM. RETRACT THE BOOM, CROWD ARM AND BUCKET. INSTALL THE BOOM HITCH
PINS AND LYNCH PINS TO LOCK THE BOOM IN PLACE. SHUT DOWN THE ENGINE, REMOVE THE
SPARK PLUG WIRE AND WAIT 5 MINUTES BEFORE PERFORMING ANY MAINTENANCE PROCEDURE
OR INSPECTION ON THE BACKHOE.