GOLDCUP CONTROLS SERIES 200
CODE 2A CYLINDER CONTROL
S23-12338
”A” Mounting CCW Rotation pump
“B” Mounting CW Rotation pump
S23-12340
”A” Mounting CW Rotation pump
“B” Mounting CCW Rotation pump
S23-12326
”B” Mounting motor
S23-12329
”A” Mounting motor
DESCRIPTION
DISASSEMBLY
See Figure 2A
PREPARATION FOR ASSEMBLY
REWORK OF WEAR PARTS
ASSEMBLY
These controls provide the capability of hydraulically selecting pre-set displacements.
On pump controls, the control is spring biased toward zero displacement. Maximum
and minimum displacements are adjustable from zero to full. On motor controls, the
control is spring offset toward full displacement. Maximum and minimum displace-
ments are adjustable from 1/3 stroke to full. Stroking pistons engage a pin on the
servo arm. When signal pressure is applied to the piston opposite to the spring, the
piston moves, causing the control arm to move to the other position. With a lever
attached to the input shaft, displacement may be manually controlled between these
two limits when there is no control signal
1. Remove screws (2). Remove control from pump. Examine servo plate for exces-
sive scratching. Note if orifices in stem are open. If servo plate is scratched or orifices
appear to be plugged, remove plate and servo stem by removing two socket set
screws from plate, then alternately loosening the two button head screws under the set
screws.
2. Remove retaining ring (4) and press the shaft assembly through the valve body.
3. Examine shoes (8) and (25) for contamination in balance pads or excessive
scratching on faces. Note: the two shoes are not identical and must be installed in the
proper position on reassembly.
4. Remove the plug (18) with attached parts. Remove the spools (15) and/or (22),
and spring (16). Observe spools and bores for free motion, wear or contamination
All parts are to be inspected and free of material defects, dirt, scratches or any foreign
material. All parts are to be cleaned with a suitable cleaning solvent and all cores and
passages blown out with clean dry compressed air.
After cleaning and inspection, all parts are to be covered with a light film of oil and
should be protected from dirt and excessive handling until assembled onto the unit.
During assembly, lapped and ground surfaces should be kept lubricated and protected
from nicks or surface damage.
1. Apply pipe sealant and Install plug (12) in body. Torque to 100 lbs-in. (11.3 Nm)
2. Press spring pins (23) into body, being careful not to mar the surface in the area of
the shoe path.
3. Install O-ring in groove of shear seal (8). Install shear seal with O-ring in the large
hole on the servo link, on the servo shaft side. Be certain that the shear seal is sitting
with the flange flush against the servo link surface.
4. Install needle bearing (9) over servo shaft and seat against the servo link. Install
10
Description Rework
Servo plate face Fine stone to remove raised burrs & dings
Shear seal Fine stone to remove raised burrs & dings. Note:
grooves to supply balance pads must be present
and adequate.
Control cover Stone or lap inside face to remove raised burrs &
dings.
Spool Break sharp edges or dings.
Note: The shear seal will fit in one position only. Otherwise one side will be held up
by the lip of the servo link. Shear seal (8) must be installed to face against the cover
plate (10). This shear seal differs from shear seal (25) in that the face surface is ma-
chined with two .094” (2.4 mm) radius scallops.
