Operation Manual
84
Faults Features
Causes
Solutions
Insufficient boom lifting
force or bucket force
1.
Worn or damaged oil seal of
oil cylinder
2.
The distribution valve is
excessively worn, and fitting
clearance between the valve rod
and valve body exceeds the
specified valve
3.
Oil
leakage
in
pipeline
system
4.
Severe
inner
leaking
of
working pump
5.
Improper
adjustment
of
safety valve and too low system
pressure
6.
Blocked oil suction pipe and
oil filter
1.
Replace the oil seal
2.
Remove, overhaul and repair to get
the clearance to the specified value and
replace the distribution valve
3.
Find out the oil leakage and remove
the fault
4.
Replace the working pump
5.
Adjust the system pressure to the
specified value
6.
Clean the oil filter and renew the oil
Pressure in air reservoir
decreases rapidly after
parking
1.
The air brake intake valve
gets stuck by dirts or damaged
2.
Loosened
pipe
joint
or
broken pipeline
3.
Poor sealing for air inlet
one-way valve of air reservoir
poor
sealing
for
pressure
controller
1
、
Blow
off
the
dirt
by
several
successive brakings and replace the
valve
2
、
Tighten the joint and replace the
brake hose
3
、
Check for the causes of poor sealing
and replace if necessary
Pressure on the brake
air
pressure
gauge
increases slowly
1.
Loosened pipe joint
2.
The air compressor works
abnormally
3.
Drain
plug
of
oil-water
separator is not fastened
4.
Poor sealing for intake valve
or drum membrane of brake
valve
5.
Blocked air-bleed hole of
pressure controller or air leaking
at
check
valve
or
drum
membrane
1
、
Tighten the joint
2
、
Check working conditions of air
compressor
3
、
Fasten again
4
、
Check and clean inside of brake
valve to find out the cause of poor sealing
5
、
Clean the air-bleed hole, find out the
causes for poor sealing of check valve
and drum membrane and remove the
fault
Air leakage for brake
system
1.
Pollution to the air source:
oil, water, dust and impurities
2.
Unacceptable
brake
fluid
has been used
3.
Air leakage caused by worn
leather ring
1.
Clean the pipeline
2.
Use acceptable brake fluid
3.
Clean the cylinder block and replace
the piston leather ring
Brake failure
1.
No or little fluid in the oil cup
2.
Oil inlet valve and hydraulic
1.
Add oil to the oil cup
2.
Replace the oil inlet valve and
