Finish Thompson VKC5.5,6,6H,7,8,10 SERIES - Manual (Page 3)

3
WeT end InSPeCTIOn / RePlaCeMenT
1 Disconnect the power. Unwire the motor (mark the wires for correct
rotation upon reassembly). Close the suction and discharge valves,
and remove the pump from the installation. Remove any discharge
piping that will hinder the removal of the housing.
2. Place the pump on a clean work bench and secure the motor or
mounting plate. Gently tap the locking ring (item 11) towards the motor
until it is loose (the locking ring connects the column housing adapter
(item 15) to the next section). Using a strap wrench, unthread the
column housing section turning it counterclockwise. Grasping the
discharge and pump head, pull it straight off of the pump and place it
on the bench with the suction pointing straight up.
3. Make an alignment mark on the side of the impeller housing (item 21)
and the column housing adapter (item 15) to aid in alignment during
the reassembly process. Remove the six impeller housing mounting
screws (items 22). Remove the impeller housing (item 21) and o-ring
(item 16). Grasp the impeller and remove it from the column housing
adapter (item 15).
CAUTION: Keep the drive magnet assembly (item 14) and
impeller drive (item 18) away from metal chips or particles.
Note: Keep the impeller housing o-ring (item 16) with the
impeller housing to avoid mix up during reassembly.
Figure 2
eXaMInaTIOn
1. Check the impeller drive bushing (item 17), thrust ring (item 20), ce-
ramic thrust ring and shaft for cracks, chips, scoring or excess wear.
See figure 2. Replace as required.
2. Check for loose magnets on the drive assembly or rubbed areas on
the impeller or column housing adapter assemblies. Contact your
distributor or FTI Technical Service if a problem is found.
BUSHIng RePlaCeMenT
1. To remove the bushing, insert 1/16” pin punch into balance hole (inner
circle of 4 holes) of impeller assembly (items 17,18,19,20). Gently
tap the bushing out of the back of the impeller assembly. The punch
may need to be moved to a different hole if the bushing is difficult to
remove.
2. To replace the bushing, clean the impeller bore. Insert the new bushing
into the back of the impeller assembly by aligning the bushing with
the impeller bore. Press gently until the bushing bottoms out (use a
block of wood and mallet if necessary).
Mount pump in desired configuration. Securely fasten mounting
plate if used. Motor feet may also be used for mounting.
PIPIng
1. Support piping near the pump to eliminate any strain on the pump
casings. Do not use suction or discharge piping to support the pump.
2. Do not overtighten the piping on the discharge on initial installation (i.e.,
down to the collar on NPT housings or the o-ring on BSP housings).
Damage to the discharge can occur. The o-ring on the BSP housing is
only used when the plastic threads are loose.
3. Do not place the pump suction directly on the bottom of the tank. Keep
the pump suction at least one pipe diameter off the bottom.
4. A suction extension tube of up to nine feet in length can be added.
5. To minimize head loss from friction:
a. Increase pipe size by 1 diameter.
b. Use minimal number of pipe bends.
6. If a check valve is installed in the discharge piping, an air bleed must
be installed in the discharge line to prevent air lock. This allows air
trapped in the pump internals to be removed on initial start-up. See
drawings 3 and 4 in Figure 1.
7. Maintain a flooded suction. Use a foot valve if necessary.
8. Ensure that the piping does not leak and suction is not prone to clog-
ging. Use a strainer if necessary on the suction.
9. If flexible hose is preferred, use reinforced hose rated for the proper
temperature and pressure. This helps avoid collapse or kinks.
10. Install valves a minimum of 10 pipe diameters from the pump.
CAUTION: To stop the pump if prime is lost, use one of the
following: (1) pressure switch on the discharge or (2) motor
minder to monitor motor current.
INSTALLATION
The VKC Series is a versatile pump designed to be operated in a va-
riety of mounting configurations. The pump can be mounted either
inside or outside of a tank or sump. See Figure 1.
Note: Drawings for illustration only. Pumps need to be properly
supported when installed.
eleCTRICal
1. Install the motor according to neC requirements and local
electrical codes. Motor should have an overload protection
circuit.
2. Wire the motor for clockwise rotation when facing the fan
end of the motor.
3. To verify the correct motor rotation:
a. Install the pump into the system
b. Fully open the suction and discharge valves
c. allow fluid to run into the pump. do not allow the pump
to run dry (PTFe and ceramic bushings can’t be run dry
without causing damage to internal parts).
d. Jog the motor (allow it to run for only one to two seconds)
and observe the rotation of the motor fan. Refer to the
directional arrow by the electrical box if needed.
Note: A pump running backwards will pump but at a greatly
reduced flow and pressure.
OPERATION
1. Completely open discharge valve. On pumps equipped with a discharge
MOTOR RePlaCeMenT
Remove the four bolts and washers (items 6, 7, and 8) securing the
motor adapter (item 9) to the motor. Carefully pull the pump away
from the motor face. loosen the two setscrews on the coupling
half (located on the motor shaft). Remove the coupling half. Install
motor shaft coupling half onto a new motor following the assembly
instructions on page one for 56C or metric frame pumps. Make
sure the coupling insert meshes. Install pump onto the new motor.