2
WINDING RESISTANCE VALUES
HP
SPEED
VOLTS
PH.
WINDING RESISTANCE IN OHMS
BLACK TO
WHITE
BLACK
TO RED
RED TO
WHITE
2
3450
230
1
1.5
3.9
5.4
2
3450
208
1
1.15
3.29
4.44
The motor windings have a fixed resistance value and must be close to those
given in chart. To check winding resistance values, disconnect pump cord
from control panel and measure resistance at cord end. Refer to control panel
instructions for complete wiring diagram.
T1
Common
Black
T4
Main
White
T5
Auxiliary
Red
MAINTENANCE
If pump does not operate properly, consult the Troubleshooting table. If trouble
cannot be located with the steps shown, consult your pump dealer or take
pump to a Little Giant authorized service center. Grinder pump is to be cleaned
and sanitized prior to returning pump to Little Giant.
CAUTION:
When working on pump or switch, always disconnect pump power
cord in addition to shutting off circuit breaker before working on pump.
CLEANING CUTTER ASSEMBLY,
VOLUTE AND IMPELLER
CAUTION:
When working on the pump, always disconnect power cord in addi-
tion to shutting off circuit breaker before working on pump and always wear
eye protection.
WARNING:
Do not remove motor house seal plate socket head cap screws.
The motor section of the pump is permanently lubricated with dielectric oil and
sealed at the factory. Removal of these socket head cap screws by anyone
other than an authorized service center will break the seal and void the war-
ranty.
WARNING:
The pump should be thoroughly cleaned of all debris and deposits
before disassembling.
WARNING:
This pump is equipped with a cutting mechanism that has very
sharp edges. Caution should be used when working on or near these parts.
1. Lay pump on its side on a smooth hard surface. Prior to removing the
volute, scribe a mark between the seal plate and volute. To gain access
to the rotating cutter, remove the volute by removing the three flange hex
head cap screws. Remove volute by
carefully tapping
and prying the
volute off the seal plate.
NOTE:
Do not damage the seal plate and volute mounting surfaces.
2. To gain access to the stationary cutter, remove the retaining ring by remov-
ing the three flange hex head cap screws.
NOTE:
The stationary cutter can
be removed from the volute without having to remove the volute.
3. Remove the stationary cutter from the volute. If the stationary cutter is
worn, it can be turned over once to utilize the other cutter edge. If the
stationary cutter is damaged, it must be replaced.
4. Under good light, inspect the two edges of the rotation cutter. If the rota-
tion cutter edges appear dull, pitted or otherwise damaged, it should be
replaced.
5. Removing the rotation cutter: Secure the impeller from rotation. Using a
rubber mallet, tap the rotation cutter to cause it to unscrew in a counter-
clockwise direction. Localized heating may help loosen the cutter.
CAUTION:
Exercise care in handling the cutter.
6. Thoroughly inspect the motor shaft and rotation cutter threads and remove
any residue and debris. Chase the shaft with a 1-12 UNF die if necessary.
7. Prior to installing the new rotation cutter, make sure the impeller is tightly
screwed on the motor shaft. Securing a large straight screw driver in the
end of the motor shaft, gently tap on the impeller vane using a rubber mal-
let (clockwise). Apply a drop of Loctite 242 to the new rotation cutter thread
and install the cutter on the motor shaft. Secure the shaft with the screw
driver and tap the rotation cutter tight onto the impeller pilot and flush with
the mating surfaces.
8. Install the stationary cutter into the volute. Reassemble the cutter retaining
ring with the three flange hex head cap screws, torque to 100 in-lbs (11
N-m).
A check valve anti-siphon valve must be used in the discharge line to prevent
back flow of liquid into the basin. The check valve should be a free flow valve
that will easily pass solids.
A gate valve should follow the check valve to allow periodic cleaning of the
check valve or removal of the pump.
The remainder of the discharge should be as short as possible with a minimum
of turns to minimize friction head loss. Do not restrict the discharge to sizes
below 1-1/4" diameter.
WIRING
Check local electrical and building codes before installation. The installation
must be in accordance with their regulations as well as the most recent National
Electric Code (NEC).
This pump should be connected or wired to a dedicated circuit with no other
outlets or equipment in the circuit line. The circuit breaker should be of ample
capacity in the electrical circuit. See chart below:
H.P.
VOLTAGE
CIRCUIT BREAKER AMPS
2
230
20
2
208
20
Figure 2
Figure 1
