Gorman-Rupp Pumps PA6C60C-B-E50 460/3 1528569 and up - Manual (Page 49)

PA SERIES OM-06531
MAINTENANCE & REPAIR PAGE E - 22
sprocket and up through the slot in the mounting
flange (18, Figure 5).
Use a suitable hoist and sling to position the air
compressor assembly (8) on the mounting flange
(9, Figure 4). Slide the belt (15) over the air com­
pressor sprocket. Use a pry bar to raise the com­
pressor high enough to install the spacers (14) be­
tween the compressor and the mounting flange.
Secure the compressor to the mounting flange
with the hardware (8, 9 and 10). Reinstall the guard
(7) and secure it with the hardware (11, 12 and 13).
(Figure 1)
Install the coupling half on the impeller shaft. Using
a suitable lifting device, position the pump end as­
sembly on the base. Align the coupling halves and
reinstall the attaching hardware. Align the coupling
as described in Installation, Section B. Install the
coupling guard (6) and secure the guard to the
drive flange with the previously removed hardware
(2 and 3).
Reinstall any leveling shims used under the pump
casing mounting feet. Secure the pump assembly
to the pump support assembly (31) with the pre­
viously removed hardware (29 and 30).
Back Cover and Wear Plate Installation And
Adjustment
(Figures 3 and 12)
If the wear plate (20) was removed for replace­
ment, carefully center it on the back cover (27) and
secure it with the hardware (21 and 22).
Lubricate the O‐rings (13 and 19) with light grease
and install them in the grooves in the wear plate
and back cover.
Clearance between the impeller and wear plate is
adjusted using four back cover nuts (25) and lock­
ing collars (23). There are 18 detents on the I.D. of
each locking collar. Indexing the collars one detent
on the adjusting screws represents approximately
.005 inch (0,13 mm) of wear plate clearance. The
recommended clearance between the wear plate
and the impeller is .010 to .020 inch (0,25 to 0,50
mm).
USE TWO
OPPOSING
BACK COVER
NUTS TO PRESS
BACK COVER
INTO PUMP
CASING USE TWO REMAINING
ADJUSTING SCREWS AND
LOCKING COLLARS TO SET
FACE CLEARANCE
TURN INDEX COLLARS
3 DETENTS COUNTER‐
CLOCKWISE, THEN
TURN CLOCKWISE UN­
TIL SCREW HOLES
ALIGN
Figure 12. Installing and Adjusting Back Cover
Screw the four adjusting screws (24) into the
tapped holes in the back cover plate until they are
just flush with the machined surface on the back
side of the cover plate.
Align the back cover plate over the studs (18) 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 (7