STA-RITE MPE Owner's Manual page 11

If shaft seal is worn or damaged, repair as follows:
Pump Dissasembly/Removing Old Seal
Disconnect power to pump motor.
Be sure valves on suction and return piping are
closed before starting work.
Release all pressure by opening all vents before starting
work.
1. Drain pump by removing drain plugs on bottom of
pump body and trap body.
2. Be sure there is no pressure in trap body; remove
cover (unscrew by turning counterclockwise).
3. Remove 6 nuts, lockwashers and flat washers holding
seal plate to pump body. Pull seal plate and motor
away from pump body. (You may have to CAREFULLY
use a screwdriver to separate body from seal plate.)
4. Remove seven screws and washers holding diffuser to
seal plate. Remove diffuser.
5. Remove motor canopy. Being careful not to touch ca-
pacitor terminals, loosen capacitor clamp and move
capacitor to one side.
6. Hold shaft with 7/16" open-end wrench on motor
shaft flats.
7. Unscrew impeller from shaft (turn counterclockwise
when facing it).
NOTICE: On 2 HP model, remove impeller screw
(left hand thread - turn clockwise) and gasket before
removing impeller. Inspect gasket for damage,
cracks, etc. Replace if damaged.
8. Remove four screws holding seal plate to motor.
9. Place seal plate face down on flat surface and tap out
ceramic seat (Figure 6).
10. Remove slinger from motor shaft and inspect for dam-
age or abrasion.
11. Clean seal cavity in seal plate and clean motor shaft.
Mechanical seal
ceramic seat
Figure 6
Pump Reassembly/Installing New Seal
1. Ceramic seat must be clean and free of dirt, grease,
dust, etc. Wet outer edge with small amount of liquid
detergent; press ceramic seat into seal plate cavity
firmly and squarely with finger pressure (Figure 7).
Polished
surface
Figure 7
2. If ceramic seat will not locate properly, remove it,
place face up on bench and reclean cavity. Ceramic
seat should now locate.
3. If seat still will not locate properly, place a cardboard
washer over the polished face and use a piece of 3/4"
(19mm) standard pipe for pressing purposes.
NOTICE: Be sure not to scratch or mar polished sur-
face or seal will leak.
4. Replace slinger on end of motor shaft so that impeller
sleeve will push it into position. If slinger shows signs
of wear or damage, replace it.
5. Remount seal plate on motor. Tighten bolts to 60-80
inch-lbs. (69-92 kg/cm) torque.
6. Apply a small amount of liquid detergent to inside di-
ameter of rotating half of seal.
7. Slide rotating seal member, polished carbon face out,
over impeller sleeve until rubber drive ring hits back
of impeller.
NOTICE: Be sure not to nick or scratch polished seal
face; seal will leak if face is damaged.
8. Screw impeller onto shaft (clockwise); this will auto-
matically locate seal in seal plate.
NOTICE: On 2 and 2-1/2 HP models; install impeller
gasket and lock screw (left-hand thread - turn coun-
terclockwise). Torque lock screw to 50-55 inch-lbs.
(57.6-63 kg/cm).
9. Mount diffuser on seal plate; tighten screws to 10-14
inch-lbs. (11.2-16.1 kg/cm) torque.
10. Assemble motor and seal plate to pump body with
nuts, flat washers and lock washers. Torque nuts to
120-130 in-lbs. (138-150 kg/cm).
11. Prime pump according to instructions on Page 9.
11
Rubber
surface