Rebuild
3A0231E
19
8.
Remove the Screws (36), that hold the Needle Block
Assembly (29) to the Inlet Block (34). The Needle
Block Assembly (29) may look different than the
illustration as it may have multiple needles. If the
needle is a removable #10-32 or Luer Lock type
consider removing it to protect it.
9.
Remove and inspect the gasket (30). If it is in good
condition you can re-use it; otherwise, discard it and
secure a replacement.
10. Remove the Screws (37) that attach the Inlet Block
(34) to the Main Body (27). If necessary for clean-
ing, remove any adapter fitting (not shown) that may
be installed in the Inlet Block (34).
11. Remove the o-rings (28).
12. Remove the four Screws (18) and the End Cap (19)
on each side of the valve. Disconnect the short air
line sections on each side.
13. Remove the two Spool Shift Pistons (21) from the
End Caps (19). They should come out easily but if
not use low pressure (less than 2 psi or 0.1 bar) air
at the Tee Fitting (17) to move them. Remove the
U-cup seals (4) from the Spool Shift Pistons (21).
14. At the top of the valve, remove the four Screws (1)
and remove the Drive Cylinder End Cap Assembly
(2). Disconnect the air line from the Tee Fitting (17).
15. Separate the Dispense Piston (3) from the Metering
Rod (11).
16. Remove the two U-cup seals (4) from the Dispense
Piston (3).
17. Remove O-ring (5) from the Divorced Section (10).
18. Remove the Screws (16) that hold the Divorced
Section (10) to the Main Body (27) and remove
O-ring (15).
19. Remove the Metering Rod (11) and Seal Cup (12)
from the Divorced Section (10).
20. Push the Seal Cup (12) off the Metering Rod and
remove the Posipak seal (13).
21. Use snap ring pliers to remove Retaining Ring (6)
and Washer (7) from the Divorced Section (10).
Remove the U-cup seal (8).
22. Remove the Dispense Sleeve (14) from the Main
Body (27).
23. Remove the Screws (20) that hold the Seal Plate
Cups (26) to each side of the Main Body (27). The
Seal Retainer Washers (22), and the Posipak Seals
(23) will come off with the Seal Plate Cups.
24. Push the Spool Assembly (24) out with a finger. If it
does not slide out, tap it gently using a wood or
plastic dowel.
Assembly
Refer to F
. 8 on page 18 for part references in the fol-
lowing procedure.
Clean all valve parts with an appropriate solvent prior to
reassembly. Always install new, lubricated o-rings and
seals when assembling the valve. Use Krytox 203GPL
(part number 84/0200-K3/11) for lubricating valve parts
including seals and o-rings. Check the Metering Rod
(11), Dispense Sleeve (14), and Sleeve Assembly (24)
for wear and if they are worn secure replacements
before proceeding.
Carefully install new U-cup and Posipak seals so that
they are not pinched or torn. Do this by making sure
they are lubricated, and by tucking the lips of the seal
inward before uniformly pushing them into position.
Install the Seal Plate Cups on the Main Body
1.
Install a lubricated O-ring (15) on the left side of the
Main Body (3) next to the sleeve part of the Spool
Assembly (24).
2.
Install two lubricated Posipak Seals (23) in the left
Seal Plate Cup (26) so that the O-ring side of both
Posipaks will be facing the Main Body (27). Be sure
to tuck the lip of the Posipak into its cavity to avoid
tearing it.
3.
Position the left Seal Cup Plate (26) with the oil cup
upwards and slide it over the Spool part of the Spool
Assembly (24) with the counterbore for the Seal
Retainer (22) facing out. Slide the Seal Retainer
(22) over the Spool and install two Screws (20).
4.
Repeat steps 3, 4 and 5 for the right side Seal Plate
Cups.
