Instruction 2111-801C 01-04 7
NOTE: As a precaution against contamination, State Departments of Health do not permit connecting the
water seal line of a sewage pump directly to the city supply.
3. Gland Adjustment:
Packing boxes should be watched for leakage of sealing water. A "weep" from the packing boxes while
pump is running is necessary to keep packing cool and in good condition. If serious leakage or no leakage
is noted, the packing gland should be tightened or loosened as required by turning the packing glands nuts
evenly a few turns only. Do not draw packing glands too tight. After adjusting packing glands, turn the shaft
by hand to be certain it rotates freely. If serious leakage will not stop, packing is probably burnt, worn, dried
out or hard and should be replaced. (Remember that when replacing packing; replace all of the packing
both above and below the lantern ring.) All packing should be renewed periodically to prevent scoring of
shaft or shaft sleeve; see paragraph on "Packing Boxes, Packing, and Packing Seals" on Pages 5 and 6.
NOTE: If upon removing the old packing, the shaft or shaft sleeve is found to be scored, then it will become
necessary to replace the shaft or shaft sleeve before installing new packing.
4. Mechanical Seal:
For Optimum life of the mechanical seals, flow thru water lubrication is required. The water enters the seal
chamber from the power frame end. The double seal housing should be vented using the petcock prior to
starting the pump. This will insure that no air is trapped within the mechanical seal chamber. CAUTION:
Never run the mechanical seal dry, as damage will result.
Each seal consists of a rotating element and a stationary element. The sealing faces are highly lapped
surfaces of materials selected for low coefficient of friction and resistance to corrosion by the liquid being
pumped. The faces have a minute running clearance and normally run on a very thin film of liquid. The
sealing liquid (preferably clear water) is injected into the seal box cartridge through a tapped connection at a
pressure higher than that which would exist in the box, thereby isolating the sealing faces from the liquid
being pumped. If sufficient sealing pressure is not maintained the pressure within the pump will force open
the lower seal and allow the liquid being pumped to enter the box, ruining the seal. A flow of 2 GPM per
pump at 5 psi above the shutoff pressure is required for satisfactory seal operation. Consult the typical
performance curve to determine shutoff head, or contact your CHICAGO PUMP representative. A solenoid
installed in the downstream side of the seal box should open the seal water line at the mechanical seal
before the pump starts. A flow meter or flow indicator installed on the seal water line at the mechanical seal
will verify flow of seal water into the seal box. A pressure reducing valve and needle valve can be used to
adjust pressure, and flow rate.
As the seal is a precision made product, care must be taken in handling. The carbon and ceramic parts
should be safeguarded from drops or severe blows. Particular care should be taken to avoid scratching the
lapped faces on the washer and floating seal.
STEADY OR INTERMEDIATE GUIDE BEARINGS:
(See Fig. 1) Steady bearings are provided with Alemite Fittings for grease lubrication, and should be
lubricated with grease having the same consistency as the lubricant recommended for the pump. Steady
bearings ordinarily need greasing every: 3 to 6 months.
UNIVERSAL JOINT COUPLINGS:
(See Fig. 1) Universal joint bearings and slip splines are provided with Zerk Alemite Fittings for grease
lubrication, and may be lubricated with the same grease recommended for steady bearings. They need
greasing only rarely, once a year usually being sufficient.
CAUTION: Pull motor disconnect before lubricating.
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