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Reassembly:
Caution: The precision lapped faces on the mechanical seal are easily damaged. Handle
your replacement seal carefully.
Thoroughly clean all surfaces of the seal seat cavity.
Using a clean cloth, wipe the shaft and shaft sleeve and make certain that they are perfectly
clean.
Wet the rubber portion of the new seal seat with a light coating of soapy water. While
wearing clean gloves or using a clean light rag, press seal seat squarely into adaptor recess.
Avoid scratching the white ceramic surface. If seat will not position properly, place a
cardboard washer over the polished surface and use a piece of pipe to press in firmly but
gently.
Dispose of cardboard washer. Check again to see that ceramic surface is free of dirt and all
other foreign particles and that it has not been scratched or damaged.
Wet the inside rubber portion of the new seal head with a light coating of soapy water. Slide
head onto the motor shaft with the sealing surface facing the seal seat. Reinstall any
shims, which have been removed. (See below for Shim Adjustment)
Thread the impeller onto the motor shaft and replace the impeller seal before screwing the
impeller nut into place.
Reassemble the pump.
A short “run-in” period may be necessary to provide completely leak proof seal operation.
Shim Adjustment:
When installing a replacement impeller (Ref 7) or motor (Ref 1), it may become necessary to
adjust the number of shims (Ref 8) to insure proper running clearance between the impeller and
the casing. Proceed as follows:
Note: A proper running clearance is between 0.015” and 0.020” (.38mm and .5mm).
For impeller replacement, add one (1) shim in addition to those removed originally.
For motor replacement, add two (2) shims in addition to the shims removed during
disassembly.
Reassemble the pump as described in Steps 2 and 3. (See above for Reassembly)
Important: Insure that the casing is snugly in place and check the shaft to make sure it
is turning freely. (Use the screwdriver slot in the motor to turn the shaft). If it turns
freely, check to insure that the casing cover and casing fitted “metal to metal” where
they meet on the outside. If they are not “metal to metal”, tighten the fasteners (Ref 13)
and recheck the shaft for free turning. Tighten carefully turning the shaft while
tightening so that the motor bearings are not damaged in the event that too many shims
were installed. If shaft seizes before fasteners are completely tight, disassemble the
pump and remove one (1) and repeat reassembly.
