F-1031, Section 4214
Page 5 of 10
Inspection and Repair
Impeller and Wear Rings
Check wear rings and impeller hubs for deep grooves or scratches. Spirol
grooves or grooves parallel to the impeller shaft increase leakage. Inspect
for excessive wear ring clearance. Diametric clearances in excess of .027
inches may warrant wear ring replacement. Original factory clearance is
.019 to .023 diametrically. The diametric clearance should be determined
by averaging the results of four measurements taken at 90 degree incre-
ments as follows:
Clean and remove small burrs or other protrusions from the wear ring inner
diameters and the impeller hub O.D. and I.D. Position each wear ring
on the impeller hub on which it was used. Hold the wear ring firmly against
one side of the hub and measure total clearance on the opposite side,
using a feeler gauge. Do not bottom the wear ring against the bottom of
the groove in the impeller.
Ball Bearings
When cleaning bearings, bearing manufacturers recommend placing them
in a basket and suspending the basket in a container of solvent, preferably
overnight. Avoid rotating the bearings before solid particles are removed,
to prevent damaging races and balls.
After cleaning, spin them immediately in light oil and check each one as
described below:
5. Examine bearing for rusted or pitted balls, races or cages.
6. Check cage and races for cracks or other damage. Examine balls and
races for brinelling, abrasion and serious discoloration. If in doubt
about condition of bearing, replace it.
7. Rotate bearing slowly, and check for roughness or excessive internal
looseness. If a rough spot is found, it may be dirt caked on a race.
Try cleaning it again. If endplay is doubtful, compare it with a new
bearing. If the bearings are not to be installed right away, wrap them
in clean, oil proof paper.
