Multiquip Submersible Pump ST4125G - Manual (Page 23)

ST4125G/ST6125G SUBMERSIBLE PUMP• OPERATION MANUAL — REV. #0 (11/18/10) — PAGE 23
MAINTENANCE
Impeller Removal
Refer to the the following procedure and Figure 19 for the
removal of the impeller.
1. Remove oil plug (item 193) and o-ring (item 194). Drain
oil from oil chamber as referenced in Figure 18.
2. Remove suction strainer/ring stand (item 84A).
3. Remove the six suction cover bolts and washers (items
188A/188B) that secure the suction cover (item 189)
to the pump housing (item 50). Remove suction cover
(item 189).
4. Remove impeller cap nut (item 188) and washer (item
66) from motor shaft.
5. Remove impeller (item 49), gap washer (item 49A) and
impeller key (item 9A) from motor shaft.
6. Reassemble in reverse order.
Figure 19. Impeller Removal
Long Term Storage
1. Area must be free from excessive humidity, corrosive
gases, vapors or vibrations which might damage the
pump.
2. Store pump in a vertical position on a pallet or stand.
3. Coil up the cable, and seal the open end (control box
wires) with waterproof tape or a cable cap. This will
prevent moisture from penetrating into the motor which
could cause severe damage to the windings.
4. Give all unpainted surfaces a light coat of oil or grease
to prevent corrosion.
5. If new pumps are stored for more than two months, turn
the impeller by hand every two months to prevent the
mechanical seal faces from seizing up. Failure to do this
may result in seal damage when the pump is started.
Water Tank Storage
1. If an installed pump (immersed in water) has not
been in operation for a long period of time, check the
insulation resistance and run the pump for 30 minutes
every month.
If the pump cannot be run due to lack of water in the
tank inspect the pump and turn the impeller by hand
each month and prior to putting the pump back into
service. If insulation drops below 10 megohms, contact
an authorized Multiquip service center.
NOTICE
Clearance between impeller and wear plate should
be between .011~.019 in. (0.3~0.5 mm). If impeller is
defective or badly worn, replace immediately.