Gorman-Rupp Pumps PA6C60-4045H 1416490 thru 1485125 - Manual (Page 44)

PA SERIES OM−06081
MAINTENANCE & REPAIR PAGE E − 24
the back cover into the pump casing until the wear
plate just touches the impeller when the shaft is
turned by hand. Tighten the nuts evenly to avoid
binding.
With the wear plate just touching the impeller, turn
the two free adjusting screws until they engage the
pump casing. Position the locking collars over the
adjusting screws so the holes in the collars for the
locking screws align approximately with the holes
in the cover plate.
Loosen the back cover nuts used to press the back
cover into the pump casing one full turn.
Pull the collars off the adjusting screws, index them
three detents counterclockwise, and reinstall the
collars on the adjusting screws. Use the collars to
turn the adjusting screws clockwise until the holes
in the locking collars realign with the tapped screw
holes in the back cover plate. Secure the locking
collars to the back cover plate with the hardware
(33 and 34). Install the two remaining back cover
nuts snugly against the adjusting screws.
Remove the first two back cover nuts from their
studs. Turn the adjusting screws clockwise until
they engage the pump casing. Install the locking
collars (17) and hardware (33 and 34). Reinstall the
back cover nuts.
Be sure the wear plate does not scrape against the
impeller.
Over time it may be necessary to repeat the adjust-
ment process to compensate for normal wear be-
tween the impeller and wear plate. When all of the
adjustment has been used on the back cover side
of the pump, an additional 0.120 inch (3 mm) of ad-
justment may be obtained by removing the rotat-
ing assembly adjusting shims (11).
Allow an installed pump to completely cool before
draining liquid from the pump casing. Remove the
back cover. Remove the rotating assembly adjust-
ing shims, then reinstall the hardware securing the
rotating assembly to the pump casing. Perform the
back cover adjustment procedure described
above to obtain the proper face clearance.
Discharge Check Valve Reassembly And
Installation
(Figure 3)
The flapper and gasket are the only serviceable
parts of the check valve. If the flapper requires re-
placement, remove the hardware securing the
cover and gasket. Separate the valve cap and re-
place the flapper.
Install the valve cap gasket and secure the cap with
the previously removed hardware.
Apply a small amount of light grease to the gasket
to hold it in place and position it against the pump
casing flange. Position the discharge check valve
assembly and secure it with the prevousily re-
moved hardware.
Priming Chamber Assembly And Installation
(Figure 7)
Clean and inspect the components of the priming
valve (1). Inspect the linkage and ensure the orifice
button (not shown) squarely engages the valve
seat. Replace the orifice button if required (see
Priming Chamber Removal and Disassembly
for orifice button removal).
If the orifice button was removed, screw the new
orifice button into the linkage bar until fully seated.
Align the hole in the linkage bar with the holes in the
bracket and reinstall the pivot pin. Secure the pivot
pin with the previously removed e-clip".
Adjust the orifice button seating as necessary by
screwing the orifice button into or out of the linkage
bar. Proper adjustment is achieved when the ori-
fice button fully seats against the orifice before the
linkage bar on the float bottoms against the
threads on the orifice button. When adjustment is
complete, install and tighten the lock washer and
hex nut securing the orifice button.
Install the strainer (6) and priming valve gasket (4).
Lower the float into the priming chamber (5) and
secure the priming valve with the previously re-
moved hardware (2 and 3).
(Figure 6)
Install the baffle (9) and gasket (8) and use a sling
and suitable lifting device to position the priming