Product Manual

MQ62TK SERIES TRASH PUMP • OPERATION AND PARTS MANUAL — REV. #0 (01/30/18) — PAGE 37
PUMP MAINTENANCE
PUMP VACUUM TEST
Perform the following procedure to test the pump vacuum.
Refer to Figure 20.
1. Remove the pump fill cap and fill the pump casing
with water.
2. Start the engine as described in the Operation section,
and wait for the pump to begin pumping.
3. Place a water hose inside the discharge port, and turn
on the water. The flow of water into the discharge port
will prevent the pump from running dry.
4. Place the pump vacuum tester (P/N 7000030) over the
suction port with the vacuum gauge facing upward. It
may be necessary to apply a small amount of water
around the rubber seal of the vacuum tester to create
a proper seal.
5. Make sure there are no air leaks between the vacuum
tester and the suction port. If air leaks are present, reset
the vacuum tester.
6. Run the pump for a few minutes while monitoring
the vacuum gauge. A gauge reading of 20–29 inHg
(inches of mercury) indicates that the pump is working
properly. A gauge reading below 20 inHg indicates that
the pump is not working properly.
7. To test the flapper valve, shut down the engine. The
vacuum tester should remain attached to the suction
port by vacuum, indicating that the flapper valve is
seating properly and holding water in the suction hose
when the engine is stopped. This prevents backflow and
allows for faster priming when the engine is restarted.
WARNING
NEVER remove the fill cap while the pump is hot. Water
inside may be under pressure.
NOTICE
25 inHg (inches of mercury) translates into 25 feet of
suction lift at sea level.
IMPELLER ADJUSTMENT
To ensure optimum pump priming and performance
standards, the proper clearance between the impeller and
the volute must be maintained. Every six months, or after
prolonged dewatering operations, check the clearance
between the impeller vanes and the outer volute surfaces.
The impeller should be as close as possible to the volute
without touching it.
For optimal performance, the recommended clearance
between the impeller and the volute is 0.10 to 0.20 inches.
The clearance can be inspected by utilizing a feeler gauge
and accessing the area via the discharge or fill port.
Adjust the clearance between the impeller and the volute
by adding/removing shims (P/N 0852836439) behind the
impeller.
PUMP CLEANING
After pumping water with a large quantity of dirt and debris,
perform the following procedure to clean the pump:
1. Remove the drain plug from the pump housing to drain
any water remaining in the pump.
2. Loosen the four locking knobs by turning them
counterclockwise. Grip the clean-out cover handles,
twist counterclockwise, and pull outward to open the
clean-out cover.
3. Clean inside the pump casing and remove all dirt
and debris. Inspect the impeller and volute for wear.
Replace any damaged or worn parts.
NOTICE
Removing too many shims will create excessive
clearance between the impeller and the volute, resulting
in reduced pump performance.
As the impeller wears down over time, additional shims
may be required to maintain minimal clearance between
the impeller and the volute.
CAUTION
The impeller can develop sharp edges. BE CAREFUL
when cleaning around the impeller to prevent injury.