Operator
’s Manual Backhoe Series BH
- Page 59 of 91 -
Version 2.0
Problem:
Cause:
Solution:
The maximum swing
action cannot be
obtained.
•
Bent piston rod in cylinder.
•
Replace or rebuild the cylinder; replace damaged
parts.
•
Something is jamming the
swing linkage.
•
Remove interference.
Slow operation of
machine (lack of power)
all cylinders.
•
Low oil supply in reservoir -
•
Fill to the proper level.
•
Oil viscosity is too heavy, or oil
is not at operating temperature
•
Use recommended hydraulic fluid.
•
Insufficient pumping.
•
Advance engine throttle.
•
Diverter valve on prime mover
leaking externally or bypassing
oil internally through the valve
to the reservoir.
•
The diverter valve may need rebuilding or
replacing.
•
Excessive back pressure.
•
Relief condition. Maybe restriction from outlet to
reservoir.
•
Relief valve setting in backhoe
control valve too low or
defective.
•
Check the relief pressure valve and make
corrections. The Backhoe system pressure is 2100
psi. Clean the relief valve or overhaul; or replace
the entire cartridge. See important instruction §
7.8.1.
Spongy or jerking action
of cylinders and/or noisy
operation.
•
Low oil supply in reservoir.
•
Fill to the proper level.
•
Air in system.
•
Bleed all air circuits by operating the machine at
maximum oil flow and complete movements.
•
Oil viscosity is too heavy, or oil
is not at operating temperature
•
Use recommended hydraulic fluid. Run the
machine until the oil reaches operating
temperature.
•
Pump not running
•
Check the pump drive to be sure it is engaged.
Lift, crowd, or bucket
cylinders dropped under
load when control spools
shifted from neutral.
•
Damaged or worn spool seals.
•
Replace spool end seals.
•
See important instruction § 7.8.1.
•
Problems involving the control
valve:
•
See important instruction § 7.8.1.
Load drops or settles.
•
Loose oil line connections,
leaks in line, or broken pipes.
•
Tighten all hose connections and replace damaged
O-rings at leaking O-ring fittings. Check and
replace any damaged hoses and lines.
•
Oil bypasses cylinder piston,
scored piston, worn piston
packing, or defective piston
assembly.
•
Replace or rebuild the cylinder; replace damaged
parts.
•
Worn or damaged rod seals on
cylinder; external repack
cylinder.
•
Rebuild cylinder, replacing damaged parts as
necessary.
•
Worn control valve.
•
Replace the control valve.
•
Damaged or worn spool seals.
•
Problems involving the control
valve.
•
Replace spool end seals.
•
See important instruction § 7.8.1.
Summary of Contents for BACKHOE BH6
Page 1: ...Operator s Manual BACKHOE SERIES BH6 BH7 BH8 VERSION 2 0 EN 2022...
Page 6: ...Operator s Manual Backhoe Series BH Page 6 of 91 Version 2 0...
Page 89: ...Operator s Manual Backhoe Series BH Page 89 of 91 Version 2 0 Excavation Specifications BH6...
Page 90: ...Operator s Manual Backhoe Series BH Page 90 of 91 Version 2 0 Excavation Specifications BH7...
Page 91: ...Operator s Manual Backhoe Series BH Page 91 of 91 Version 2 0 Excavation Specifications BH8...
