Specifications

GOLDCUP CONTROLS SERIES 500
PROCEDURE FOR CLEANING
FILTER
DISASSEMBLY OF BRAKE AND
BYPASS PORTION
See Figure 5C-1
PREPARATION FOR ASSEMBLY
REWORK OF WEAR PARTS
ASSEMBLY
See Figure 5C-1
6. Connect electrical signal and zero the electrical driver “zero adjustment”.
7. Restore shuttle valve and system pressure settings to original operating conditions.
A screen in the servo inlet line to the stroker prevents particles from getting into the jet
pipe which might plug the jet pipe. In older versions, this screen is behind the plug,
(13). Field service is not recommended, as contaminants are on the outside, and
could become dislodged in the servo body upon removal. In later versions the screen
is behind the fitting supplying servo oil to the stroker, and contaminants are lodged
inside. With caution, it is possible to clean this filter as follows:
1. Disconnect servo tube line. Remove control from pump.
2. Remove plug (13).
3. Blow filtered air into the opening under the plug. Observe for air from the servo
connection.
4. Force filtered oil or a compatable solvent through the opening to flush contaminants
from the screen and out the servo inlet connection.
5. Carefully remove the filter without dislodging dirt into the opening. In latest version,
this filter is retained by a drilled hex plug. Backflush as before by forcing filtered oil
into the port behind plug (13). Clean and install filter.
6. Examine surface of control cover for excess scratching. Examine shear seal for
contamination in balance pads or deep scratches. Stone lightly to remove raised burrs
and dings. Check that grooves supplying servo oil to balance pads are open.
7. Place two spring washers (31-6), nested with the bent sections matching each
other, into the large hole in the servo link.
8. Place washer (31-10) against the spring washers.
9. Install O-ring (31-8) into groove in the shear seal (31-7). Install shear seal Place
on top of washer, (31-10). Position shear seal to match the lip on the servo link.
10. If control is to be tested on unit, install on control pad with new gasket and new
Nyltite washers under screws. Torque to 30 lbs- ft. (40.8 Nm). Connect bypass tubing
lines. Connect servo line and electrical connector to stroker.
1. Remove plugs (28). Remove springs (27), pistons (26), and spools (22), with
attached parts. Do not disassemble unless parts are damaged. Examine spools, pis-
tons and bores for free motion, wear or contamination.
2. If trimmer adjustment must be removed, carefully tap the spring pin (17) in till flush
with O.D. of screw (16). Remove nut (18), and screw (16). Remove spring pin (17)
from screw.
3. Remove bypass valve body (36) with fitting (38) piston (39) and spring (34).
Remove plug (32) and spring (31). Remove spools (30) and (33).
4. Remove shoe (45), and spring (44).
5. Blow through passages to check two orifices (11) and orifice (10) in body for conta-
mination. Check passages in body for free flow.
All parts are to be inspected and be free of material defects, dirt, scratches or any for-
eign 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. Install orifices (10) and (11) in body. Torque to 25 lbs-in. (2.8 Nm). Make sure that
the orifice (11) in the deeper bore extends past the wall of the valve bore and will not
interfere with spool (33) or spool (22) action.
2. Apply pipe sealant and install plugs (14) in body. Torque to 100 lbs-in. (11.3 Nm)
3. Press pin (15) into screw (16) to 0.38” (9.65 mm) extended length.
4. Install screw (16) into body. Pin (15) should extend into spool bore approximately
.090” (2.29 mm). The eccentric pin must be indexed so that it is offset towards the out-
side surface of the cover plate. The drilled hole for the spring pin (17) should be
approximately centered in the slotted opening in the cover plate. Install spring pin (17)
into trimmer assembly. Leave approximately one-half length of pin extending from
37
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.
Shoe Stone to remove raised burrs or dings.