Gorman-Rupp Pumps PA6C60C-F4L 1504811 and up - Manual (Page 48)

PA SERIES OM-05768
MAINTENANCE & REPAIR PAGE E - 26
Align the back cover plate over the studs (20) and
slide it into the pump casing. Use two back cover
nuts on diagonally opposing studs to press the
back cover into the pump casing until the wear
plate just touches the impeller when the shaft is
turned by hand. Tighten the hand 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
(13 and 35). Install the two remaining hand knobs
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 and hardware (13 and 35). 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 (14).
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)
If the discharge check valve (26) was disas­
sembled to replace the flapper or cover O‐ring,
position the flapper in the valve body and check to
ensure free movement.
Install the valve cover O‐ring and secure the cover
to the body with the previously removed hardware.
Apply a small amount of light grease to the dis­
charge flange gasket to hold it in place and posi­
tion it against the pump casing flange. Support the
discharge check valve assembly using a sling and
a suitable lifting device. Using the previously re­
moved hardware, secure the discharge check
valve assembly and flange gasket to the pump as­
sembly (1).
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