PA SERIES PUMPS
MR−05702
MAINTENANCE & REPAIR
PAGE C − 18
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 C−3)
Remove the four capscrews and hex nuts (not sup-
plied) securing the seal plate to the intermediate.
With the volute casing (1) resting on a flat surface
and the suction opening facing down, secure a
suitable lifting device to the bellhousing mounting
holes in the intermediate (14).
Install a new gasket (32) over the volute studs (8).
Use the lifting device to carefully lower the rotating
portion of the pump over the volute studs until fully
seated against the volute.
NOTE
Position the rotating portion of the pump over the
volute studs so the air vent (13) is properly oriented
with the volute casing (see the volute orientation de-
tails, Figure C−3).
Secure the volute casing to the intermediate with
the hardware (9 and 10).
Suction Head And Wear Ring Installation And
Adjustment
(Figure C−3)
Lubricate the O-rings (34 and 39) with grease and
install them in the grooves in the wear ring (41).
Make sure the adjusting screws (37) are fully re-
tracted, and press the wear ring into the suction
head until fully seated and the mounting holes in
the wear ring align with the mounting holes in the
suction head. Secure the wear ring to the suction
head with the hardware (35 and 36). Do not over-
tighten the mounting hardware. Over-tightening
the hardware can deform the wear ring, resulting in
uneven clearance with the impeller.
Slide the assembled suction head and wear ring
into the pump casing with the suction head mount-
ing foot positioned as shown in the volute orienta-
tion detail for your pump in Figure C−3. Secure the
suction head to the pump casing with the hard-
ware (45 and 46).
Reach through the suction opening and use a feel-
er gauge to measure the gap between the wear
ring and the impeller. This clearance should be be-
tween .010 and .020 inch (to mm).
To adjust the clearance, loosen the hardware se-
curing the wear ring to the suction head. Loosen
the jam nuts (38) and turn the adjusting screws
(37) clockwise in an alternating pattern until the
proper clearance is achieved. When the clearance
is correct, tighten the jam nuts and the securing
hardware.
Suction Spool Flange Installation
(Figure C−1 or C−2)
Apply a light coating of grease to one side of the
suction spool flange gasket (3, Figure C−1 or 4,
Figure C−2) and use the grease to secure the gas-
ket to the pump casing flange.
Use a suitable lifting device to position the suction
spool flange (7, Figure C−1 or 8, Figure C−2)
against the gasket. Secure the flange to the pump
casing with the hardware (4, 5 and 6, Figure C−1
or 5, 6 and 7, Figure C−2).
Secure the flange to the base with the previously
removed hardware (not shown).
Discharge Check Valve Assembly and
Installation
(Figure C−2)
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.
Support the discharge check valve assembly (3)
using a sling and a suitable lifting device. Secure
the discharge check valve assembly and gasket
(13) to the pump assembly (1) using the hardware
(9, 10, 11 and 12)
