Be sure the new seal material is compatible with the fluid being pumped.
Packing-type seals are normally replaced when their leakage becomes excessive.
(More than two or three drops per day.) Place a sheet of clean paper under the seal
to check this.
Remove the packing gland from the shaft. After pulling off the packing rings, inspect
and clean the shaft. Follow the manufacturer's procedures to install the new rings
(Figure 5-1 9).
Pumps with packing-type seals should not be used with solar fluids.
When the pump is first started, fluid should run freely from the packing. Tighten the
packing gland bolts one-half turn at a time so the tightening is uniform. Tighten until
the leakage is close to the manufacturer's recommendation.
When replacing mechanical seals, remove the impeller from the shaft. After pulling
off the old seal, inspect and clean the shaft. Follow the manufacturer's procedures
for installing the new seal and facing surfaces, if used. Be sure to compress the
spring adequately when replacing the impeller (Figure 5-20).
5.2 REPAIR PROCEDURES