Pulsafeeder Isochem GM12 Series, Installation, Operation, & Maintenance Instruction

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10
end of the pump drive shaft (Item 4) and slide
the driven magnet assembly (Item 18) off the
drive shaft. The key (Item 8) and other retaining
ring can also now be removed.
9. Remove the housing nuts (Item 16) and the
rear housing (Item 1).
10. Remove the center housing (Item 2). The
gears (Items 6, 7) and wear plates (Item 11)
are now accessible and can readily be
removed along with the drive and idler shafts
(Item 4, 5).
11. The gears can be removed from the shafts by
removing one of the retaining rings and sliding
the gear off the shaft.
12. Inspect all parts for signs of wear or damage.
The maximum diametrical clearance (bearing
J.D. -
shaft 0.0.) that is acceptable is .010
inches (.254mm). Shafts and bearings that are
scored or worn must be replaced. Gears and
wear plates with excessive wear or scoring
must also be replaced.
13. Clean all parts before reassembly.
REASSEMBLY
1. Install the drive and idler gear (Items 6, 7) onto
their respective shafts (Items
4, 5) using keys
(Item 8) and retaining rings (Item 14). Take
care not to scratch the shafts when installing
the rings. Check the ends of the rings for sharp
burrs. If a plastic and metal gear set are being
used, the plastic gear is always the idler gear.
2. With the housing pins (Item 13) in the locator
holes in the front housing (Item 3) and new O-
rings (Item 12) installed in the center housing,
assemble on the center housing (Item 2).
3. Install a pair of wear plates (Item 11) and the
shaft assemblies.
4. Next install another pair of wear plates, housing
pins and the rear housing (Item 1). Install the
housing bolts (Item 15) and nuts (Item 16) and
tighten.
5. Install the following parts onto the pump drive
shaft in the order listed: retaining ring (Item 14),
key (Item 8), driven magnet assembly
(Item 18) with the short, hub
side towards the front housing and retaining ring.
(Item 14). Note: Only new retaining rings should
be used on the driven magnet end due to the
bending required at disassembly. Use caution
not to bend these rings during assembly.
6. Place a new O-ring (Item 28) onto the pilot on
the front housing and place the can (Item 19)
over the O-ring. Next pilot the casing (Item 20)
over the can and thread in hand tight the front
housing bolts (Item 26). Gradually and evenly
tighten the front housing bolts to draw the
casing and front housing together. Take care
not to pinch the O-ring. Replace the protective
plugs.
7. Install the spool (Item 29) onto the motor.
Then install the drive magnet assembly (Item
21) onto the motor shaft to the dimension
shown in Figure 3. If the motor is metric slide
the drive magnet assembly onto the motor shaft
until it butts up against the shoulder on the
motor shaft. Tighten the drive magnet
setscrews (Item 24) through the hole provided
in the spool to 75 inch lbs. (847 Ncm). These
setscrews have a special nylon patch applied to
the threads to prevent loosening.
8. Carefully assemble the motor/spool/drive
magnet assembly to the pump casing. Be
careful not to chip the drive magnets when
slipping them over the can or to pinch your
fingers when the two assemblies snap together.
The use of (4) assembly guide pins (Part #
49639) is suggested. Use guide pin (Part #
49656) for metric motors. See Figure 2.
Install casing bolts (Item 35).
9. Reinstall pump in system, open inlet and
discharge valves and start pump. Monitor pump
for 5-10 minutes for signs of binding, excessive
noise and motor amperage draw. Check
performance. If problems are encountered refer
to the Troubleshooting Section.