8
Cleaning,
Inspection
and Repair
REMEMBER:
Zenith metering pumps
are made for exacting duty. In order to
develop high pressure and minimize slip
flow, the clearance between the metering
gears and the housing must be as small
as possible, yet large enough to allow
adequate lubrication. All parts are
machined to extreme accuracy. Critical
dimensions are held between one and
two ten-thousandths of an inch (2 to 5µ).
Consistent performance is dependent
upon proper handling.
Please handle the pumps with extreme
care and set aside a separate clean area
for pump maintenance and repair.
It is recommended that pump users
institute a program for dimensional
inspection of critical parts in order to
keep maintenance and operating costs to
a minimum. By noting the performance of
a pump immediately before removing it
from service and correlating the perfor-
mance to measured component wear,
the maximum wear limits for the pump’s
critical components can be established.
Additionally, the service life of the pump
can be predicted and downtime can be
scheduled accordingly.
If necessary, any Zenith precision
metering pump requiring maintenance
can be returned to the factory for complete
repair and overhaul. For a large number
of pumps, Zenith offers a contract repair
service, which helps to reduce repair
costs and delivery time. Zenith Pumps
also offers pump maintenance seminars.
For more information concerning Zenith
pump repair services, please contact our
Customer Service Department.
C-9000 Series
Disassembly
Instructions below assume the pump
has been removed from the system, for
example magnetically driven pumps with
adapter plates have been disengaged
from the housings.
Note: As parts are disassembled, place them
carefully on a clean surface such as a soft
cloth. See Figure 3. Do not allow them to
touch each other. Pay close attention to the
order in which parts are removed. This will
aid in the reassembly of the pump. The
numbers in parentheses refer to the part
numbers on the bill of materials.
Caution:
Please review the precautions
listed on Page 7 for Magnetically
Coupled Pumps.
1.
If the pump came with an outer drive
gear, remove it from the drive shaft
before starting disassembly.
2.
Remove the square key (17) from
the shaft end.
3.
If applicable, remove the socket head
screws (18) from the seal housing (11).
See
Figure 4.
4.
Lift off the seal housing (11). Take care
to also remove the o-ring (33) which
seals the housing to the front plate. The
ring may be attached to the front plate.
5.
Remove the seal (51) [item 13 on
4.5 & 9 cc/rev pumps] from the seal
housing (11).
a)
Mechanical Face Seal Pumps; The
ceramic seat of the mechanical face
seal may be removed from the seal
housing by pushing it out with finger
pressure. If it is stuck, use two small
Allen keys or other small pins to press
the seat from the housing using the two
access holes in the housing face. Set
screws will have to be loosened to allow
removal of the mechanical seal (13)
from the drive shaft. Some materials of
the seal (face) are brittle in nature, use
extreme caution so as not to damage
the seal or its components. Remove the
retaining ring (16) from drive shaft with
a brass or plastic tool.
b)
Double Lip Seal Pumps; Press the lip
seal (51) [item 13 on 4.5 & 9 cc/rev
pumps] from the housing using finger
pressure, or by pressing on the seal
using a plastic tool.
Figure 3
Figure 4
