Gorman-Rupp Pumps PAH6B60-6068H 1507875 and up - Manual (Page 44)

PAH SERIES OM-06451
MAINTENANCE & REPAIR PAGE E - 22
and secure it to the bearing housing with the hard­
ware (15 and 16).
Press the stationary element and its O‐ring into the
seal plate until fully seated in the seal plate bore. A
push tube cut from a length of plastic pipe would
aid this process. The I.D. of the tube should be
slightly larger than the O.D. of the shaft sleeve (7).
Install the shaft sleeve O‐ring (8) in the groove in
the I.D. of the sleeve. Lubricate the O‐ring and the
O.D. of the shaft sleeve with “P-80
R
Emulsion” or
water. Do not use oil or any substitute lubricant
other than water.
Slide the rotating subassembly (consisting of the
rotating element, retainer and bellows) onto the
sleeve until the rotating element is just flush with
the chamfered end of the sleeve. Slide the shaft
sleeve and rotating subassembly onto the shaft
until the seal faces contact and the shaft sleeve
seats against the shoulder on the impeller shaft.
Install the seal spring and spring centering washer.
Lubricate the seal assembly as indicated in
LUBRICATION, after the impeller has been in­
stalled.
Impeller Installation And Adjustment
(Figure 5)
Inspect the impeller (1) and replace it if cracked or
badly worn.
Install the same thickness of adjusting shims (5) as
previously installed. Install the impeller key (26) in
the shaft keyway. Align the keyway in the impeller
with the shaft key and press the impeller onto the
shaft until fully seated.
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.
Apply `Loctite Retaining Compound No. 242' or
equivalent to the threads of the impeller capscrew
(2). Install the roll pin (4) in the hole in the impeller.
Position the impeller washer over the end of the im­
peller shaft so the hole in the washer aligns with the
roll pin. Block impeller rotation as described in Im­
peller Removal and torque the impeller capscrew
to 180 ft. lbs. (24,9 m. kg.).
Pump Casing Installation
(Figure 5)
Lubricate the O‐ring (3A) with light grease and in­
stall it in the groove in the O.D. of the seal plate.
Install a lifting eye in the uppermost hole in the
pump casing (1) for the pipe plug (5). Be sure to
screw the lifting eye tightly into the hole as far as it
will go. Attach a sling and suitable lifting device to
the lifting eye and use the lifting device to position
the pump casing over the rotating assembly. Install
the hardware (8 and 9) on the studs (7) and use the
hardware to fully seat the pump casing against the
seal plate (9, Figure 5).
Suction Head and Wear Ring Installation and
Adjustment
(Figure 4)
If the wear ring (10) was removed, position the re­
placement wear ring in the suction head (2) and
use an arbor (or hydraulic) press to press it into the
suction head until fully seated.
Install the O‐ring (3) in the groove in the O.D. of the
suction head and lubricate it with light grease.
Position the suction head over the studs (11).
The clearance between the wear ring and the im­
peller is adjusted using the four back cover nuts
(16) and locking collars (13). There are 18 detents
on the I.D. of each locking collar. Indexing the col­
lars one detent on the adjusting screws represents
approximately .005 inch (0,13 mm) of wear plate
clearance. The recommended clearance between
the wear ring and the impeller is .008 to .015 inch
(0,2 to 0,4 mm).
Screw the four adjusting screws (12) 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.
Use two back cover nuts on diagonally opposing
studs (11) to press the suction head into the pump
casing until the wear ring just touches the impeller
when the shaft is turned. Tighten the back cover
nuts evenly to avoid binding.
With the wear ring just touching the impeller, turn
the two free adjusting screws until they engage the
pump casing. Position the locking collars over the