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OM-06575
PA SERIES
PAGE B - 6
INSTALLATION
Tighten the belts in accordance with the belt manu
facturer's instructions. If the belts are too loose,
they will slip; if the belts are too tight, there will be
excessive power loss and possible bearing failure.
Select pulleys that will match the proper speed ra
tio; overspeeding the pump may damage both
pump and power source.
Do not operate the pump without the
guard in place over the rotating parts
.
exposed rotating parts can catch cloth
ing, fingers, or tools, causing severe in
jury to personnel.
DRIVE BELT TENSIONING
General Rules of Tensioning
For new drive belts, check the tension after 5, 20
and 50 hours of operation and re‐tension as re
quired (see the following procedure for measuring
belt tension). Thereafter, check and re‐tension if re
quired monthly or at 500 hour intervals, whichever
comes first.
Ideal drive belt tension is the
lowest
tension at
which the belt will not slip under peak load condi
tions. Do not over‐tension drive belts. Over‐ten
sioning will shorten both drive belt and bearing life.
Under‐tensioning will cause belt slippage. Always
keep belts free from dirt, grease, oil and other for
eign material which may cause slippage.
COLD WEATHER INSTALLATION
If the pump is to be installed in an environment
where sub‐freezing temperatures will occur during
operation, consideration must be given to prevent
the pump and components from freezing when the
pump is idle between pumping cycles. With Gor
man‐Rupp priming assisted pumps, there are two
methods of accomplishing this.
One method is through the use of an optional heat
ed priming chamber, which is available as a facto
ry‐installed option or as a retrofit kit for most mod
els (consult the factory). This method pumps heat
ed liquid from the engine cooling system through
the priming chamber to heat the chamber and its
contents. This method is particularly effective
where pumping cycles are short enough to ensure
that the liquid in the priming chamber never fully
freezes.
The second method involves configuring the
pumping system to drain both the priming cham
ber and pump casing after each pumping cycle.
With no liquid remaining in the system, freezing
cannot occur.
To configure the pump to drain between pumping
cycles, the first step is to remove the check valve
from the line that runs between the top of the prim
ing hopper and the priming venturi. This check
valve is located close to the venturi end of the line.
Remove the check valve, then reconnect the line
directly to the venturi. This will allow air to enter the
pump through the top of the priming hopper when
the pump shuts off, providing for complete
drainage of the pump and priming hopper.
Next, install a drain line between the pump drain
and the wet well or sump. This line must remain
submerged in the liquid below the pump down lev
el of the liquid level control device; otherwise, the
pump may not prime. If the application involves liq
uids that could clog the drain line, make sure to
check the line periodically to ensure it remains
open; otherwise, liquid could remain in the casing,
resulting in freezing and potential damage to the
pumping system.
Configuring the system to drain between cycles
will help ensure that the pump will not freeze during
cold weather applications.
However, it should be
noted that the time required for the pump to be
gin to discharge liquid will increase, as the
pump will have to fully re‐prime at the beginning
of each pumping cycle.