moyno 20302, Service Manual

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TROUBLE SHOOTING
WARNING: Before making adjustments,
disconnect power source and
thoroughly bleed pressure from
system. Failure to do so could result
in electric shock or serious bodily
harm.
Failure To Pump.
1.
Belt or coupling slip: Adjust belt tension or tighten
set screw on coupling.
2.
Wrong rotation: Rotation must be clockwise when
facing shaft.
3.
Excessive suction lift, vacuum or obstruction in
suction piping
.
4.
Flexible joint broken; possible excessive
pressure:
Replace joint, check pressure at discharge port.
Will Not Start.
1.
Insufficient horsepower: Check motor starting
torque for minimum model starting torque given
in
Table 1.
2.
Low voltage: Check power supply.
Pump Overloads.
1.
Excessive discharge pressure: Check discharge
pressure for maximum rating given in Table 1
above. Check for obstruction in discharge pipe.
2.
Excessive temperature: Check fluid temperature
for a maximum of 160°F.
3.
Belt or coupling slip: Check pressure at discharge
port.
4.
Loose bond in stator: High temperature and
caustics will cause bond between rubber and
tube to fail. Replace stator, check fluid
temperature and pressure at discharge port.
5.
Fluid viscosity too high: Recommended maximum
RPM.
Viscosity CP Limit RPM
1-300 1750
300-1,000 1200
1,000-2,000 700
2,000-5,000 350
5,000-10,000 180
10,000-20,000 100
6. Motor connected incorrectly: Motor wired for 230
VAC, connected to 115 VAC service.
Noisy Operation.
1. Starved suction: Check fluid supply, length of
suction line, and obstructions in pipe.
2. Bearings worn: Replace parts; check alignment,
belt tension, pressure at discharge port.
3. Broken flexible joint: Replace part; check
pressure at discharge port.
4. Insufficient mounting: Mount to be secure to firm
base. Vibration induced noise can be reduced by
using mount pads and hose on suction and
discharge ports.
Poor Performance.
1. Low pressure; worn stator: Replace stator: check
for excessive abrasive material in fluid, check for
run dry condition.
Mechanical Seal Leakage (Mechanical Seal
Models Only).
1. Leakage at startup: If leakage is slight, allow
pump to run several hours to let faces run in.
2. Persistent seal leakage: Faces may be cracked
from freezing or thermal shock. Replace seal.
Packing Leakage (Packing Models Only).
1. Leakage at startup: Adjust packing as outlined in
maintenance instructions.
Note: Slight leakage is necessary for lubrication of
packing.
2. Persistent leakage: Packing rings and/or shaft
may be worn. Replace parts as required.
Pump Will Not Prime.
1. Air leak on suction side: Check pipe connections.
Suction lift over 15 ft. will cause seal faces to
open.
2. Defective mechanical seal: Inspect and repair as
necessary.
MAINTENANCE
General. These pumps have been designed for a
minimum of maintenance, the extent of which is
routine lubrication and adjustment of packing. The
pump is one of the easiest to work on in that the main
elements are very accessible and require few tools to
disassemble.
Packing Lubrication (Packing Models Only). The
zerk fitting on the top of the packing housing leads to
the lantern ring halves in the mid-section of the
packings. At least once a week, inject a small quantity
of good quality grease, such as MPG-2 Multi Purpose
Grease (DuBois Chemical), or equivalent, into the
zerk fitting to lubricate the packings.
Packing Adjustment (Packing Models Only).
Packing gland attaching nuts should be evenly
adjusted so they are little more than finger tight. Over-
tightening of the packing gland may result in
premature packing failure and possible damage to the
shaft and gland.
When the packing is new, frequent minor
adjustments are recommended for the first few hours
of operation in order to compress and seat the
packing. Be sure to allow slight leakage for lubrication
of packing.
When excessive leakage can no longer be
regulated by tightening the gland nuts, remove and
replace the packings in accordance with the
DISASSEMBLY and REASSEMBLY instructions. The
entire pump need not be disassembled to replace the
packings.
Bearing Lubrication. The prelubricated, fully sealed
bearings do not require additional lubrication.
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