Gorman-Rupp Pumps 3D-B 883512 and up - Manual (Page 14)

OM−01490 D SERIES
OPERATION PAGE C − 2
a gearbox with A 30:36:1 ratio and a 1750
RPM maximum input drive. Make certain
that the electric motor installed does not
exceed this rpm; otherwise, pump compo-
nents may be destroyed.
Priming
The pump may not prime immediately because the
suction line must first fill with liquid. If the pump fails
to prime within five minutes, stop the motor and
check the suction line for leaks.
OPERATION CHECKS
Gearbox Check
Check that the gearbox is properly lubricated (see
LUBRICATION in MAINTENANCE AND RE-
PAIR).
Leakage Check
No leakage should be visible at pump mating sur-
faces, connections or fittings. Keep all line connec-
tions and fittings tight to maintain maximum pump
efficiency.
Strainer Check
If a suction strainer has been installed, check and
clean it as necessary. It should be cleaned if pump
flow begins to drop. If a vacuum suction gauge has
been installed, monitor and record the readings
regularly to detect strainer blockage.
Accumulator Chamber Check
Check periodically to ensure that there is sufficient
air in the integral suction accumulator chamber.
Replenish as required (see Fixed, Rigid Piping in
Section B for details).
STOPPING
After stopping the pump, shut off incoming power
to the motor and lock it out to ensure that the pump
will remain inoperative.
If the pump will be idle for more than a few hours, or
if it has been pumping liquids containing a large
amount of solids, flush it with clean water.
Cold Weather Preservation
The primary construction materials of this
pump are aluminum, with neoprene flap
valves and diaphragm. Do not attempt to
clean or flush this pump with any liquid
which would attack pump fittings or com-
ponents. avoid cleaning with cleaning sol-
vent.
In below freezing conditions, drain the water from
the pump and the lines when the pump is not in op-
eration. Also, clean out any solids by flushing with a
hose.
GEARBOX TEMPERATURE CHECK
The gearbox runs higher than ambient tempera-
tures because of heat generated by friction. Tem-
peratures of approximately 200
_F (93_C) are con-
sidered normal, and can operate intermittently at
250
_F (121_C).
Checking gearbox temperatures by hand is inac-
curate. Place a contact-type thermometer against
the housing and record this temperature for future
reference.
A sudden increase in gearbox temperature is a
warning that the bearings are at the point of failing.
Make certain that the bearing lubricant is of the
proper viscosity and at the correct level (see LU-
BRICATION in Section E). Bearing overheating
can also be caused by shaft misalignment and/or
excessive vibration.
When pumps are first started, the bearings may
seem to run at temperatures above normal. Con-
tinued operation should bring the temperatures
down to normal levels within 20 minutes or less.