Case 580ST, Operator'S Manual

Page: 385 / 434

8 - TROUBLESHOOTING
Swing
PROBLEM POSSIBLE CAUSE CORRECTION
The swing circuit relief valves are
not seating, set to a too low value or
there is a leak in the seat. Test the swing circuit relief valve.
Valve spool leaking.
Inspect the spool and check it for
wear or scratches.
Right or left swing is inoperative, is
too slow or loses power.
Cylinder seals leaking or cylinder
barrel damaged. Inspect and reseal the cylinder and
the ring nut.
Built-in sliding limiter damaged. Disassemble and inspect.
The swing fails to slow down (bearing
stop) at stroke end.
Cylinder seals leaking or cylinder
barrel damaged. Inspect and reseal the cylinder.
The circuit relief valve (return side) is
stuck open, set to a too low value or
there is a leak in the seat. Test the swing circuit relief valve. The swing does not stop when the
control lever returns to neutral (one
direction only).
Valve spool leaking. Inspect the spool and check it for
wear or scratches.
Internal valve leak.
Inspect the spool and check it for
wear or scratches. Cylinder leak (spools in neutral).
Cylinder seals leaking or cylinder
barrel damaged. Inspect and reseal the cylinder.
A circuit temporarily lowers when
given the control to lift. Load check valve between control
valve sections damaged. Disassemble and inspect.
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