Service manual

19
SEAL CHAMBER PRIMING:
Fill mechanical seal chamber with liquid to insure seal does not start dry. This can be done by
removing seal vent set-screw and pouring fluid into seal vent before opening pump inlet.
Alternately, seal chamber can be vented in situations where inlet pressure is above
atmospheric by opening inlet and discharge valves and then loosening seal vent plug to allow
positive inlet pressure to push air out of seal chamber until oil flows from it. See Figure 13.
Seal chamber priming for 3E model pumps with mechanical seals:
For the Imo 3E Model pumps with mechanical seals, there is no seal vent port. The mechanical
seal in these model pumps is located in the discharge chamber of the pump and is in the fluid
flow path. In these model pumps the complete pump must be filled and vented of any trapped
air prior to starting the pump. Contact the factory if you have questions. See Figure 8 on page
12 and Figure 12 on page 18 of this manual for suction piping and pump filling methods.
Figure 13 – Filling or Venting Seal Cavity Using Seal Vent
CAUTION
• Failure to fill or vent seal chamber as described above may cause damage to
seal running faces which may result in seal leakage.
E.10 START-UP
It is suggested that driver be started and immediately stopped (jogged) three or four times in
order to verify proper pump rotation and to insure pump is filled with liquid. Open bleed port at
high point in system and vent trapped air until a solid stream of liquid emerges (where
practical). When pump is running, check for unusual noise or vibration. Investigate any
abnormalities. Check inlet and outlet gages to see if pump is operating within its ratings.
Generally in most pump types, differential pressure across the pump should be a minimum of
40 psi to insure proper pump operation; this pressure may vary based on specific pump types. It
is highly recommended that more specific guidance be requested from the factory if this
information has not been previously provided.
WARNING
• Precautions must be taken when venting air in system using hazardous liquids.
• Provide hearing protection whenever high noise levels are expected from
system components and/or environment.
• If operating temperatures exceed 140° F (60° C), measures should be taken to
avoid skin contact.