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

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8
GMC2
& GMC4 SERIES
REFERENCE DRAWING: SD2579
DISASSEMBLY
1. Close discharge and suction valves.
2. Disconnect power source to motor.
3. Flush and drain pump then remove pump from
the piping. Do not forget to drain the can area
through the front housing drain plug (Item 27).
4. Remove motor bolts (Item 25). Metric motors
use an extra motor adaptor (Item 29) and
require that the adaptor bolts (Item 30) be
removed first.
5. Separate the motor and casing (Item 20) by
pulling them apart. This will take physical force
because you are pulling against the magnetic
attraction of the drive to the driven magnet. Do
not pry but pull straight apart.
6. Do not remove the drive magnet assembly
(Item 21) from the motor unless it or the motor
are to be replaced. This will make reassembly
easier later. The drive magnet assembly is
removed by loosening the setscrews (Item 24)
and sliding it off the motor shaft.
7. Remove the recessed front housing bolts (Item
26). You must first remove the protective plug.
This will allow the casing and can (Item 19) to
be separated from the front housing (Item 3).
Note: Any remaining fluid left in the can will
now drain out.
8. Remove the retaining ring (Item 14) on the 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
(Items 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
I.D. - shaft O.D.). 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).
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.