Gorman-Rupp Pumps 54J20-B 1410811 and up - Manual (Page 18)

OM-01342 50 SERIES
OPERATION PAGE C - 2
because the suction line must first fill with liquid. If
the pump fails to prime within five minutes, stop it
and check the suction line for leaks.
After the pump has been primed, partially close the
discharge line throttling valve in order to fill the line
slowly and guard against excessive shock pres­
sure which could damage pipe ends, gaskets,
sprinkler heads, and any other fixtures connected
to the line. When the discharge line is completely
filled, adjust the throttling valve to the required flow
rate.
Do not operate the pump against a
closed discharge throttling valve for
long periods of time. If operated against
a closed discharge throttling valve,
pump components will deteriorate, and
the liquid could come to a boil, build
pressure, and cause the pump casing to
rupture or explode.
Leakage
No leakage should be visible at pump mating sur­
faces, or at pump connections or fittings. Keep all
line connections and fittings tight to maintain maxi­
mum pump efficiency.
Liquid Temperature And Overheating
The maximum liquid temperature for this pump is
160
_
F (71
_
C). Do not apply it at a higher operating
temperature.
Overheating can occur if operated with the valves
in the suction or discharge lines closed. Operating
against closed valves could bring the liquid to a
boil, build pressure, and cause the pump to rup­
ture or explode. If overheating occurs, stop the
pump and allow it to cool before servicing it. Refill
the pump casing with cool liquid.
Allow an over‐heated pump to com­
pletely cool before servicing
. Do not re­
move plates, covers, gauges, pipe
plugs, or fittings from an overheated
pump. Liquid within the pump can reach
boiling temperatures, and vapor pres­
sure within the pump can cause parts
being disengaged to be ejected with
great force. After the pump cools, drain
the liquid from the pump by removing
the casing drain plug. Use caution when
removing the plug to prevent injury to
personnel from hot liquid.
Strainer Check
If a suction strainer has been shipped with the
pump or installed by the user, check the strainer
regularly, and clean it as necessary. The strainer
should also be checked if pump flow rate begins to
drop. If a vacuum suction gauge has been in­
stalled, monitor and record the readings regularly
to detect strainer blockage.
Pump Vacuum Check
Since this pump does not have a suction check
valve, the discharge line must be fitted with a check
valve if a pump vacuum reading is to be taken.
With the pump inoperative, install a vacuum gauge
in the system, using pipe dope on the threads.
Block the suction line and start the pump. At oper­
ating speed the pump should pull a vacuum of 20
inches (508 mm) or more of mercury. If it does not,
check for air leaks in the seal, gasket, or discharge
valve.
Open the suction line, and read the vacuum gauge
with the pump primed and at operation speed.
Shut off the pump. The vacuum gauge reading will
immediately drop proportionate to static suction
lift, and should then stabilize. If the vacuum reading
falls off rapidly after stabilization, an air leak exists.
Before checking for the source of the leak, check
the point of installation of the vacuum gauge.
STOPPING
Never halt the flow of liquid suddenly. If the liquid
being pumped is stopped abruptly, damaging