Gorman-Rupp Pumps S4A1-E25 460/3 1396155 and up - Manual (Page 40)

S SERIES PUMPS OM-06098
MAINTENANCE AND REPAIR PAGE E - 14
be cleaned and inspected in place. It is
strongly recommended that the bearings
be replaced any time the shaft and rotor
assembly is removed.
Before removing the bearings from the rotor shaft,
clean and inspect the bearings in place as follows.
Clean the bearings thoroughly in fresh cleaning
solvent. Dry the bearings with filtered compressed
air and coat with light oil.
Most cleaning solvents are toxic and
flammable. Use them only in a well ven­
tilated area; free from excessive heat,
sparks, and flame. Read and follow all
precautions printed on solvent contain­
ers.
Rotate the bearings by hand to check for rough­
ness or binding and inspect the bearing balls. If ro­
tation is rough or the bearing balls discolored, re­
place the bearings.
The bearing tolerances provide a tight press fit
onto the shaft and a snug slip fit into the motor
housing and bearing bore. Replace the shaft and
rotor (as an assembly), the motor housing or inter­
mediate if the proper bearing fit is not achieved.
If replacement is required, use a bearing puller to
remove the upper and lower ball bearings from the
rotor shaft. Remove the bearing cap (43) and gas­
ket (45) from the rotor shaft.
NOTE
It may be necessary to use the bearing cap (43) and
capscrews (49) in conjunction with a bearing puller
to remove the lower bearing.
Stator Removal
(Figure E-1)
Do not remove the stator (39) unless it is defective
(open windings, insulation resistance low, or stator
core damaged). If the stator must be removed, re­
move the terminal housing as indicated in Termi­
nal Housing And Power Cable Disassembly.
Position an expandable tool, such as a split disc,
approximately 2 inches (51 mm) inside the stator,
and expand it tightly and squarely on the I.D. At­
tach a lifting device to the lifting eye of the tool, and
raise the assembly approximately 1 inch (25 mm)
off the work surface.
The motor housing (16) must be heated with a
torch to expand it enough for the stator to be re­
moved. Apply heat evenly to the outside of the mo­
tor housing; excessive heat is not required. Use a
soft‐faced mallet to rap alternate edges of the mo­
tor housing, and “walk” the stator out. Continue
this process until the stator clears the motor hous­
ing.
Take care not to damage the stator end
turns during removal from the motor hous­
ing.
After the stator has been removed, wrap it in clean,
dry rags or other suitable material until reassembly.
The stator must be kept clean and dry. When han­
dling the stator, do not set it on the end windings;
lay it on its side.
Do not attempt to rewind the stator. Wind­
ing tolerances and materials are closely
controlled by the manufacturer, and any
deviation can cause damage or operating
problems. Replace the stator, or return it to
one of The Gorman‐Rupp Authorized Sub­
mersible Repair Centers or The Gorman‐
Rupp factory, if defective.
Relief Valve
(Figure E-1)
It is recommended that the relief valve assembly
(28) be replaced at each overhaul, or at any time
the pump motor overheats and activates the valve.
Never replace this valve with a substitute which has
not been specified or provided by the Gorman‐
Rupp Company.
It is not necessary to remove the heavy pipe nipple
(31) to remove the pressure relief valve. If the nip­