Bell & Gossett P81845B Series 3530 Centrifugal Pumps - Manual (Page 5)

8.4.3 Remove impeller locknut (304).
8.4.4 Remove impeller (101) by turning counter-clock-
wise when looking at the front of the pump.
Protect hand with rag or glove.
8.4.5 With two pry bars 180 degrees apart and in-
serted between seal housing (184) and the motor
adapter (108), carefully separate the two parts.
The mechanical seal rotary unit (383) should
come off the shaft with the seal housing.
8.4.6 Push out the mechanical seal stationary seat
from the motor side of the seal housing.
9. REASSEMBLY
9.1 All parts should be cleaned before assembly.
9.2 Refer to parts list to identify required replacement
items. Specify pump index or catalog number when
ordering parts.
9.3 Reassembly is the reverse of disassembly.
9.4 Observe the following when reassembling the liquid-
end:
9.4.1 All mechanical seal components must be in good
condition or leakage may result. Replacement of
complete seal assembly, whenever seal has been
removed, is good standard practice.
It is permissible to use a light lubricant, such as
glycerin, to facilitate assembly. Do not contami-
nate the mechanical seal faces with lubricant.
9.4.2 Inspect casing O-ring (513) and replace if dam-
aged. This O-ring may be lubricated with petro-
leum jelly to ease
9.4.3 Inspect guidevane O-ring (349) and replace if
worn.
9.5 Check reassembled unit for binding. Correct as
required.
9.6 Tighten casing bolts in a star pattern to prevent O-ring
binding.
10. TROUBLE SHOOTING CHART
MOTOR NOT RUNNING
(See causes 1 thru 6)
LITTLE OR NO LIQUID DELIVERED:
(See causes 7 thru 17)
POWER CONSUMPTION TOO HIGH:
(See causes 4, 17, 18, 19, 22)
EXCESSIVE NOISE AND VIBRATION:
(See causes 4, 6, 9, 13, 15, 16, 18, 20, 21, 22)
PROBABLE CAUSE:
1. Tripped thermal protector
2. Open circuit breaker
3. Blown fuse
4. Rotating parts binding
5. Motor wired improperly
6. Defective motor
7. Not primed
8. Discharge plugged or valve closed
9. Incorrect rotation
10. Foot valve too small, suction not submerged, inlet
screen plugged.
11. Low voltage
12. Phase loss (3-phase only)
13. Air or gasses in liquid
14. System head too high
15. NPSHA too low: Suction lift too high or suction losses
excessive. Check with vacuum gauge.
16. Impeller worn or plugged
17. Incorrect impeller diameter
18. Head too low causing excessive flow rate
19. Viscosity or specific gravity too high
20. Worn bearings
21. Pump or piping loose
22. Pump and motor misaligned
5
CAUTION: Do not insert screwdriver between
impeller vanes to prevent rotation of close-
coupled units. Remove cap at opposite end of motor. A
screwdriver slot or a pair of flats will be exposed. Using
them will prevent impeller damage.
Failure to follow these instructions could result in serious
personal injury or death, and property damage.
CAUTION: Do not lubricant guidevane O-ring
(349). Insure it is not pinched by the impeller on
reassembly.
Failure to follow these instructions could result in serious
personal injury or death, and property damage.
CAUTION: Failure to remove the impeller in a
counter-clockwise direction may damage threading
on the impeller, shaft or both.
Failure to follow these instructions could result in serious
personal injury or death, and property damage.