Checking The Servo Valve (Control Valve) - Danfoss 20 Series Service Manual

Service Manual and
Repair Instructions
Trouble Shooting
Inspection Instructions
(continued)
Axial Piston Pumps Series 20

Checking the servo valve (control valve)

86
1. Disconnect the external control linkage from
the control handle and check for neutral
operating with control handle. Releasing
control handle should allow the pump to
return to neutral. If operation is satis factory
with external control linkage disconnected,
the problem is not in the hydrostatic
transmission.
If operation is not satisfactory with external
control linkage disconnec ted from control
handle, the control may be misadjusted.
3. Holding the control in place, and swing it
away from housing and remove. Inspect
visible linkages, tor sion spring, and O-rings.
Inspect for missing, plugged, or incorrect
orifice.
L1003506 • Rev BA • Jun 2014
F000 082
2. Remove the cap screws (see page 22).
86
78
F000 046
4. Further disassembly of servo valve is not
permitted.
89, 90 82
Orifice (81) 81 85 80 86 87 88
F000 083
F000 062
15