Section T31
Dated February 2011
Part No. 64-3520-01-588
If seal components must be reused,
carefully inspect for microscopic
cracks and nicks. Scratches that
might be ignored elsewhere can
produce leakage if they are on seal
carbons and seat wearing surfaces.
Cleanliness is imperative when
working with mechanical seals.
Almost unnoticeable particles be-
tween seal faces can be, and often
are, the cause of early seal failures.
Check the impeller; it is designed
to oat. It should move easily on
the shaft. As long as it can be
moved on the shaft by hand, it is
loose enough. If the impeller can
be rocked or wobbled, it is too loose
and must be replaced.
Check the shaft for galling, pit-
ting, and corrosion. If the shaft is
corroded where the seal comes in
contact with the shaft, the motor
or bearing pedestal shaft must be
replaced. Surface corrosion must
be removed so that seals can slide
freely during assembly. The shaft
diameter should be no smaller than
.002” below the nominal fractional
seal sizes. Remove any nicks or
burrs which may have occurred
during disassembly. Re-clean parts
as necessary.
5D Reassembly
All parts should be visually in-
spected and cleaned or replaced as
outlined in 5C above.
1. The seal seat (#125) must be in-
stalled in the motor bracket (#1)
before the bracket is installed on
the motor. To install the seat:
a. Place the motor bracket face
up on a at surface.
b. Apply a coating of compat-
ible lubricant to the elastomer
portion of the seat to aid with
installation.
c. Carefully press the seat,
smooth side up, into the seat
cavity of the motor bracket.
Thumb pressure is usually
sufcient to install the seat.
2. Installing the motor bracket.
This is best done with the motor
standing on end. Make sure that
both the “C”-face of the motor
and the feet of the motor bracket
are clean. Slide the motor
bracket over the shaft onto the
motor.
3. Installing the rotating element
(#12). Lubricate the I.D. of the
rotating element. Place the
rotating element on the shaft with
the carbon end towards the seat.
Place the spring over the shaft,
with the backing plate up, and
compress the spring to locate
the rotating element against
the seat. If this fails to seat the
rotating element gently push the
rotating element down with a thin
blade screwdriver being careful
not to damage the seat or the
rotating element.
4. Compress and hold the seal
spring slightly below the snap
ring groove and install the snap
ring (#4). Make sure the snap
ring is locked in the groove.
