JD Series
OM-05724
PAGE D - 2
TROUBLESHOOTING
TROUBLESHOOTING CHART (cont'd)
TROUBLE
POSSIBLE CAUSE
PROBABLE REMEDY
MOTOR RUNS,
BUT DOES NOT
DELIVER RATED
DISCHARGE.
INSUFFICIENT LIQUID IN WET WELL. STOP PUMP UNTIL LIQUID LEVEL RISES.
IMPELLER ROTATING IN WRONG DI-
RECTION.
CHECK IMPELLER ROTATION (
SEE SEC-
TION C
).
CLOGGED SUCTION PORT OR IM-
PELLER CAUSING MOTOR OVER-
LOAD.
CLEAR BLOCKAGE; RESET OVERLOAD
DEVICE IN CONTROL BOX.
MOTOR OVERHEATED; THERMAL
SWITCH TRIPPED.
ALLOW PUMP TO COOL.
MOISTURE SENSING DEVICE TRIP-
PED.
DISASSEMBLE PUMP AND LOCATE LEAK.
MOTOR BEARINGS DEFECTIVE.
DISASSEMBLE PUMP AND CHECK
MOTOR CABLE DAMAGED.
CHECK PER
ELECTRICAL TESTING
.
INSUFFICIENT LIQUID IN WET WELL. STOP PUMP UNTIL LIQUID LEVEL RISES.
PUMP STARTS
THEN SHUTS
OFF.
EXCESSIVE
NOISE OR VIBRA
TION.
IMPELLER CLOGGED.
CLEAR BLOCKAGE
IMPELLER LOOSE OR DAMAGED.
CHECK IMPELLER; REPLACE IF
NECESSARY.
MOTOR SHAFT OR BEARINGS
REPLACE
DEFECTIVE.
PUMPING ENTRAINED AIR.
CHECK WET WELL LIQUID LEVEL.
PUMP OPERATING OUTSIDE DE-
SIGNED OPERATING RANGE.
CHECK DISCHARGE HEAD AND FLOW:
ADJUST AS REQUIRED TO MEET PER-
FORMANCE SPECIFICATIONS.
(CONT.)
ELECTRICAL TESTING
Make the electrical checks which follow to deter
mine if pump malfunctions are being caused by
problems in the motor or in the motor cable.
Test Equipment
A volt/amp/ohmmeter and megohmmeter of ade
quate range and quality are required to conduct
the electrical
tests which follow. use the commercial equipment
listed below, or equivalent substitutes.
Refer to the wiring diagram(s) accompany
ing the motor and control box before re
connecting any electrical leads which have
been disconnected. Connections to the
