7
Dismantling Procedure (continued):
14. Remove the spring location washer (22).
15. Remove top diaphragm plate (23).
16. Carefully remove main diaphragm (9).
17. Remove diaphragm spacer (24).
18. Withdraw the valve spindle (2) through the bottom plug opening in body (3).
19. Remove "O" ring seal (30) from the valve spindle (2).
20. Withdraw valve disc holder (4) complete with valve disc (5) through bottom plug opening in body (3).
21. Unscrew the secondary diaphragm screws (25) then lift off the secondary diaphragm assembly (8), (26), (27)
& (28) through the top of the body (3).
22. Remove valve spacer (6) from secondary diaphragm assembly.
23. Remove secondary diaphragm mounting plate gasket (7).
24. Unscrew secondary diaphragm clamping plate screws (28).
25. Remove secondary diaphragm clamping plate (8).
26. Carefully remove the secondary diaphragm (27).
27. Check that hole in impulse tube (29) is clear. DO NOT REMOVE FROM BODY.
28. Wipe valve seat and body clean of any dirt particles, taking care not to damage sealing surface in body.
29. Inspect all diaphragms and soft seals and replace where necessary (a spares kit is available for this
purpose).
Rebuilding procedure:
Note: Inspect all sealing 'O' rings, diaphragms, valves discs, gaskets and replace where necessary (a soft
spares kit is available for this purpose).
The use of Molykote 111 "O" ring lubricant is recommended during the rebuild- unless for use with oxygen when
no lubricant should be used.
1.
Replace "O" ring seal (30) over threaded end of valve spindle (2) until it rests against shoulder of spindle.
2.
Assemble valve disc (5) onto valve disc holder (4) with bead uppermost.
3.
Replace valve disc assembly (4) & (5) over threaded end of valve spindle (2) with chamfer around centre
facing downward.
4.
Load valve spindle assembly (2) through bottom plug opening in body (3). This will ease assembly of valve
spacer (6) and secondary diaphragm.
5.
Replace bottom plug (1) in bottom aperture of body ensuring that valve spindle assembly (2) is located correctly.
6.
Load the valve spacer (6) through the top of the body (counter bore upwards) onto the valve spindle
assembly (2).
7.
Place the secondary diaphragm (27) on top of the secondary diaphragm clamping plate (8) with the internal
radii on the secondary diaphragm clamping plate (8) facing upward. Ensure the holes in each component
line up correctly.
8.
Place the secondary diaphragm mounting plate (26), with counterbore facing downward, onto the
secondary diaphragm (27) and secondary diaphragm clamping plate (8). Ensure the holes in each
component line up correctly.
9.
Secure secondary diaphragm mounting plate (26) to the secondary diaphragm (27) and secondary
diaphragm clamping plate (8) using screws (28) and tighten.
10.
Place secondary diaphragm mounting plate gasket (7) in position on top of flange in body (3).
11.
With heads of screws (28) on underside, place the secondary diaphragm assembly over valve spindle (2),
ensure the secondary diaphragm fits into the counterbore of the valve spacer (6). Orientate the secondary
diaphragm assembly so that the holes for screws (25) and impulse tube (29) are in line.
J48HL: Maintenance Instructions