42
EN
A world
in motion
since 1919!
KUKKO Werkzeugfabrik
Series YRH - YRE - YSM
#
description of error
Cause of error
resolution of error
22 Cylinder does not
retract at all or does so
abnormally slowly.
Pressure relief valve of
the hydraulic pump is
closed.
open the pressure relief
valve.
23
Coupling on a valve is not
completely tightened.
Check all connections
and valves and tighten
them, if necessary.
if necessary, disassemble
and reassemble the
hydraulic system.
24
oil reservoir of the hand
pump is too full.
empty the oil reservoir of
the hand pump according
to the instructions for the
hand pump.
25
A constriction in the hose
prevents the hydraulic oil
from flowing freely.
Constrictions are
usually the result of
kinks. loosen the kink or
the constricted area.
replace the hose that has
a constriction because
the casing could be
defective.
26
damage inside the
cylinder.
Switch the cylinder off.
if necessary, send it to
the manufacturer for
repair or replace it with a
new one.
27
the return spring is
defective or too weak.
Have the cylinder
serviced by the
manufacturer or by
a trained hydraulics
technician.
7. Maintenance
•
Always use dust caps when a valve is not connected.
•
Always keep the device clean.
•
Before long-term storage, the cylinder must be fully
•
retracted and extended to lubricate the internal metal parts
and protect them from corrosion. Then store the cylinder on
the pressure pad side.
•
Change the hydraulic oil at least every two years. If the
cylinder is subject to one of the following conditions, please
