Finish Thompson DB22 SERIES - Manual (Page 11)

11
Figure 19 Figure 20
Impeller Replacement
1. To remove the impeller from the inner drive magnet, gently
pry off by hand or lightly tap on the back of the impeller.
2. To install a new impeller, place the inner drive magnet as-
sembly face up. Line up the patterns on the impeller with
the ones on the inner drive magnet so they match and press
into place by hand. An arbor press can also be used to press
the impeller on the inner drive. Place a piece of wood over
the top of the impeller thrust ring and push down on the
impeller until it is completely seated in the inner drive.
Reassembly
1. Lubricate the o-ring (item 8A) with a chemically compatible
lubricant and install in the groove in the motor adapter.
2. Install the barrier (item 7) into the motor adapter (item 8).
Press firmly to ensure that the barrier is completely seated.
3. Install o-ring (item 6) in groove in
barrier.
4. Install impeller shaft (item 5) into
barrier by aligning flats on the
shaft with the ones in the barrier.
Make sure it is completely seated.
See figure 21.
Figure 21
Figure 22 Figure 23
5. Carefully install the impeller/inner drive assembly (items 3A,
3, 4, 4A) by sliding it over the impeller shaft in the barrier.
It is normal for the impeller/inner drive to pop up a slight
amount due to magnetic forces. See figures 22 and 23.
Figure 24
6. Install the impeller housing (item 1). Make sure the dis-
charge is in the correct orientation in relation to the motor
adapter pump foot. Align the shaft in the barrier with the
front shaft support in the impeller housing. Press down to
push the impeller/inner drive magnet assembly into position.
Holding the impeller housing with one hand, install and fin-
ger-tighten two bolts lock washers and flat washers (items
11, 12, 13) in opposite locations. See figure 24.
7. Install the remaining bolts, lock
washers and flat washers finger
tight.
8. Using a 19 mm socket, tighten
all the bolts evenly using a star
pattern. Tighten to 240 in-lb
(27.1 N-m)
9. Reinstall the pump on the motor/
drive magnet following instruc-
tions from “Section I – Assembly, Pumps without Motors,
Steps 5 & 8”.
1. To remove the bushing, place the impeller/inner drive
assembly (items 3A, 3, 4, 4A) with the impeller facing up
in an arbor press. If necessary support the bottom of the
assembly with blocks to allow the bushing to fall out. Insert
a 1” (25.4mm) diameter plastic or wooden shaft through the
impeller and press bushing out. See figure 19.
2. To replace bushing, place the assembly on a flat surface
with the impeller thrust ring face down. With the slotted face
of the bushing facing the rear of the inner drive, align the
flat in the bushing with the flat in the inner drive magnet.
See figure 20. Gently push until bushing bottoms out.
Bushing Replacement