Eaton Vickers DG3V-8 Series Overhaul Manual page 19

E. Pressure Centered Main Stage Disassembly
(Refer to Figure 18)
1. Remove the four attaching screws (1) from the crossover
plate (2) and remove the crossover plate from the main
stage body (3).
The following section pertains to main stage
disassembly. If your unit does not require main stage
disassembly, omit the following section.
2. Loosen the four end cover screws (6) from end cover (7).
Be ready to catch any oil trapped inside the unit. Remove
the end cover, spring (10) and discard ''O'' ring (8).
3. Remove sleeve (11) and piston (12) from the main stage
spool (9).
4. Remove main stage spool (9) from body (3).
Perform step 5 for opposite side cover disassembly. Note
that centering springs are different.
5. Loosen the four end cover screws (13) from end cover
(14). Be ready to catch any oil trapped inside the unit.
Remove the end cover, spring (15), centering washer
(16) and ''O'' Ring (17).
6. Remove plug (18) and ''O'' Ring (19) from cover (7).
7. Turn the body (3) on its side and remove ''O'' rings (20,
24, 25 and 26) from mounting face.
8. If necessary, remove rest pins (27) with vise grip pliers.
The following step pertains to integral check valve
models only. DO NOT remove check valve parts unless
inspection or unit operation indicates a check valve
problem. If check valve removal is necessary, perform
step 9.
9. See Table 7 for screw information. Obtain a piece of pipe
or tubing with an inside diameter that is slightly larger
than the outside diameter of the seat. Also obtain a flat
washer. Remove seat (21), Figure 15, per instructions
noted in Figure 15. Remove poppet (22) and spring (23).
Model Screw Dia./
Thread Type
DG4V-3(S) .5625-18
UNF-2B
Table 7. Screw Tabulation for Seat Removal
DO NOT remove the internal plugs of body unless
inspection reveals a problem.
Note
Note
Note
Screw
Length
76.2mm
(3 in.)
Note
10. Remove ''O'' rings (4) and (29), set screw (5) and plug
(28) from body (3).
Screw
Tubing
Thread seat (21), then place tubing
and washer over seat area as shown.
Thread the screw into seat (21).
Tighten the screw to remove seat.
Figure 15. Check Valve Seat Removal
F. High/Standard Performance Pilot Valve
Disassembly
(Refer to Figure 19)
The following steps describe the disassembly sequence
of a DG4V-3(S)-*A(L)/B(L)-FJ/FW-60 pilot valve.
1. Remove the four screws (1) from name plate (2) and
remove the nameplate, cover (3) and gasket (4) from the
terminal box (5). Discard gasket (4).
2. Remove two screws (7) and strap (8) from the terminal
box (5).
3 Remove two screws (9), ground screw (11), terminal box
(5) and gasket (6) from body (10). Discard gasket (6).
If the pilot valve is equipped with two solenoids, perform
steps 3 through 6 for opposite end of body (10).
4. Remove knob (12) ) from core tube S/A (21). Remove
coil (14) from body (10) and discard ''O'' Rings (13) and
(15). Unscrew core tube.
5. Remove push pin (18), spring 917), washer (19) or (20)
and ''O'' Ring (15) from body (10). Remove ''O'' Ring (16)
from core tube S/A (21).
Washer
Seat (21)
(Figure 17)
Note
Note
Note
19