SANDPIPER M15 Non-Metallic - Manual (Page 28)

m15nmdl3sm-rev0713 Model M15 Non-Metallic Page 26
Modular Check Valve Drawing MODULAR CHECK VALVE
SERVICING
Before servicing the check valves,
first shut off the suction line and then
the discharge line to the pump. Next,
shut off the compressed air supply,
bleed air pressure from the pump, and
disconnect the air supply line from
the pump. Drain any remaining fluid
from the pump. The pump can now be
removed for service.
To access the modular check valve,
remove the elbows (items 17& 18 from
pump composite repair parts drawing).
Use a wrench or socket to remove
the fasteners. Once the elbows are
removed, the modular check valves
can be seen in the cavities of the outer
chamber (items 13).
Next remove the check valve seal
(item 33). Inspect the seal for cuts
or pinched areas. Replace seal as
needed.
Disassemble the component parts of
each modular check valve. Inspect the
check valve retainer (item 29) for cuts,
abrasive wear, or embedded materials.
Replace as needed.
Inspect the check balls (items 3) for
wear, abrasion, or cuts on the spherical
surface. The check valve seats (items
35) should be inspected for cuts,
abrasive wear, or embedded material
on the surfaces of both the external
and internal chamfers. The spherical
surface of the check balls must seat
flush to the surface of the inner chamfer
on the check valve seats for the pump to
operate to peak efficiency. Replace any
worn or damaged parts as necessary.
Remove the remaining check valve
seal (item 33). Inspect the seal for cuts
or pinched areas. Replace seal as
needed.
Re-assemble the modular check
valve. The seat should fit snugly into
the retainer.
Place a check valve seal (item 33)
into the cavity of the outer chamber
(item 13). Make sure the chamfer side
of the seal faces out. Insert the modular
check valve into the outer chamber
with the retainer facing up. Install a
check valve seal (item 33). Make sure
the chamfer side of the seal faces the
chamfer on the check valve seat or
retainer.
The pump can now reassembled,
reconnected and returned to operation.