Gorman-Rupp Pumps PA6C60C-B-E50 460/3 1528569 and up - Manual (Page 48)

OM-06531 PA SERIES
MAINTENANCE & REPAIR PAGE E - 21
Impeller Installation And Adjustment
(Figure 4)
Inspect the impeller (1) and replace it if cracked or
badly worn.
The shaft and impeller threads must be
completely clean before reinstalling the im­
peller. Even the slightest amount of dirt on
the threads can cause the impeller to seize
to the shaft, making future removal difficult
or impossible without damage to the im­
peller or shaft.
Install the same thickness of impeller adjusting
shims (2) as previously removed and screw the im­
peller onto the shaft until tight.
NOTE
At the slightest sign of binding, immediately back
the impeller off, and check the threads for dirt. Do
not try to force the impeller onto the shaft.
A clearance of .025 to .040 inch (0,64 to 1,02 mm)
between the impeller and the seal plate is neces­
sary for maximum pump efficiency. Measure this
clearance and add or remove impeller adjusting
shims as required.
Pump Casing Installation
(Figure 3)
Install a pair of “S” hooks in two opposing holes in
the mounting flange (9, Figure 4). Connect a sling
and suitable lifting device to the “S” hooks.
Lubricate the O‐rings (13 and 14) with light grease,
and install them in the grooves in the bearing hous­
ing and seal plate. Use the lifting device to lower
the rotating assembly into the pump casing. Align
the holes in the bearing housing for the mounting
hardware (7 and 12) with those in the pump casing.
Install the same thickness of adjusting shims (15)
as previously removed, and secure the rotating as­
sembly to the pump casing with the hardware (7
and 12). Do not fully tighten the capscrews until the
impeller face clearance has been set.
A clearance of .010 to .020 inch (0,25 to 0,5 mm)
between the impeller and the wear plate is also rec­
ommended for maximum pump efficiency. This
clearance can be obtained by adding or removing
an equal thickness of shims from each of the rotat­
ing assembly shim sets (15) until the impeller
scrapes against the wear plate when the shaft is
turned. After the impeller scrapes, add approxi­
mately .010 inch (0,25 mm) of shims to each shim
set.
After the face clearance has been set, tighten the
hardware securing the rotating assembly to the
pump casing.
Securing Pump End to Power Source
(Figure 2)
Install the key (30, Figure 4) in the shaft keyway,
making sure to leave room in the keyway for the
drive key (31, Figure 4). Install the bushing (16)
and sprocket (17) on the shaft to the dimension
shown in Figure 11.
NOTE
When properly installed to the dimension shown in
Figure 11, the key (30, Figure 4) will not extend fully
through the bushing. This is an acceptable fit for
this application.
Figure 11. Drive Sprocket Positioning
Secure the bushing and sheave to the shaft by
torqueing the bushing screws to 23.3 ft. lbs. (280
in. lbs. or 3,2 m. kg.). Install the belt (15) over the