Baseline Systems BHM Series Hydrometer - Manual (Page 33)

Hydrometers Operation and Maintenance Manual •
33
Maintenance 6” Models, Cont.
DIAPHRAGM AND UPPER STEM BEARING
Dis-assembly
• Unscrew and remove the 12 screws (17) and remove the upper
diaphragm ring (18).
• Remove the diaphragm (19).
• Inspect for cracks or excessive wear and replace as necessary.
• Inspect the upper stem wiper (20) and replace as necessary.
• Remove the upper stem bearing (21) from inside the stem
(24). Inspect the upper stem bearing (21) along with the upper
stem bearing o-ring (22) and the stem o-ring (15). Replace as
necessary.
Re-assembly
• Replace the upper stem wiper (20) onto the upper stem bearing
(21)
• Replace the upper stem bearing (21) into the stem (24).
• Place the diaphragm (19) into the grooves on the stem (24).
• Place the upper diaphragm ring (18) over the diaphragm and
screw the 12 stem screws (17) into place.
LOWER STEM BEARING AND VALVE COVER
Dis-assembly
• Unscrew and remove the stem lock nut (29).
• Pull the valve cover (28) from the stem. Inspect the rubber for
cracks or excessive wear. Replace as necessary.
• Inspect the lower valve cover o-ring (26) and replace as
necessary. It is located in a groove inside the valve cover
opening.
• Using a screwdriver, remove the lock ring (27) from inside the
bottom of the stem (24).
• Inspect the lower stem bearing wiper (20) and the lower stem
bearing o-ring (22) and replace as necessary.
• Inspect and replace the lower stem bearing (25) as necessary.
Use a pipe wrench to remove it from the stem (24).
• Apply Loctite 270 or similar glue to the threads of the lower
stem bearing (25).
• Screw it back into the stem (24).
Re-assembly
• Replace the lower stem wiper (20) into the bottom of the stem
(24).
• Snap the wiper locking ring (27) into the stem (24).
• Push the valve cover (28) onto the lower stem bearing (25).
• Apply Loctite 270 or similar glue to the threads of the stem
lock nut (29).
• Screw the stem lock nut (29) into the stem (24). Do not over
tighten. Make sure that the valve cover is free to move up and
down slightly.