Gorman-Rupp Pumps PAH4A60-6068H 1511893 and up - Manual (Page 44)

OM-06441 PAH SERIES
MAINTENANCE & REPAIR PAGE E - 21
Shaft and Bearing Reassembly and Installation
(Figure 6)
Inspect the shaft (25) for distortion, nicks or
scratches, or for thread damage on the impeller
end. Dress small nicks and burrs with a fine file or
emery cloth. Replace the shaft if defective.
Clean and inspect the bearings as indicated in
Shaft And Bearing Removal And Disassembly.
To prevent damage during removal from
the shaft, it is recommended that bearings
be cleaned and inspected in place. It is
strongly recommended that the bearings
be replaced any time the shaft and bear­
ings are removed.
The bearings may be heated to ease installation.
An induction heater, hot oil bath, electric oven, or
hot plate may be used to heat the bearings. Bear­
ings should never be heated with a direct flame or
directly on a hot plate.
NOTE
If a hot oil bath is used to heat the bearings, both the
oil and the container must be absolutely clean. If
the oil has been previously used, it must be thor­
oughly filtered.
NOTE
Position the outboard bearing (24) on the shaft with
the retaining ring on the bearing O.D. toward the
drive end of the shaft. The inboard bearing (27) is
equipped with a flange ring that is shipped loose
with the bearing. Install the flange ring on the shaft
prior to heating and installing the bearings.
Heat the bearings to a uniform temperature no
higher than 250
_
F (120
_
C), and slide the bearings
onto the shaft, one at a time, until they are fully
seated against the shaft shoulders. This should be
done quickly, in one continuous motion, to prevent
the bearings from cooling and sticking on the shaft.
After the bearings have been installed and allowed
to cool, check to ensure that they have not moved
during cooling. If movement has occurred, use a
suitably sized sleeve and a press to reposition the
bearings against the shaft shoulders.
If heating the bearings is not practical, use a suit­
ably sized sleeve and an arbor (or hydraulic) press
to install the bearings on the shaft.
When installing the bearings onto the
shaft, never press or hit against the outer
race, balls, rollers or cage. Press only on
the inner race.
It is recommended that a new bearing lock
washer (23) be installed any time the shaft
and bearings are disassembled. Re‐use of
an old lock washer may create a pre‐load
condition on the bearing, resulting in pre­
mature bearing failure.
Install the bearing lockwasher (23) and screw the
bearing locknut (22) onto the shaft until tight.
Torque the bearing lock nut to (150 ft. lbs. (20,8 m.
kg.). After torquing, locate the tab on the lock
washer that aligns with a slot in the lock nut and
bend the tab over into the slot.
Apply a light coating of oil to the lip of the inboard oil
seal (12) and press it into the pedestal bore with the
lip positioned as shown in Figure 6. Press the oil
seal into the pedestal until the face is just flush
with the machined surface on the pedestal.
It is recommended that a sleeve be positioned
against the inboard oil seal to prevent the lip of the
oil seal from rolling as the shaft and bearings are
installed in the pedestal. The O.D. of the sleeve
should be just smaller than the bearing housing
bore, while the I.D. of the sleeve should be just larg­
er than the O.D. of the lip seal area of the shaft.
With the lip seal sleeve in place, lubricate the lip
seal area of the shaft and slide the shaft and as­
sembled bearings into the bearing housing until
the retaining ring on the outboard bearing seats
against the pedestal. Remove the lip seal sleeve.