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Pump Vacuum Test
CAUTION :
DO NOT attempt to start the engine unless the pump has previously been primed. with water. Severe pump damage will occur if pump has not been primed.
To perform the pump vacuum test do the following:
1.Remove the pump fill cap, and fill the pump with water.
2.Start the engine as outlined in the initial
3.As shown in Figure 12 (next page), place a water hose inside the discharge opening of the pump, and turn on the water. This flow of water into the discharge opening will prevent the pump from running dry.
4.Place the Pump Vacuum Tester (P/N 7000030) over the pump inlet opening (Figure 15) with the vacuum guage facing upwards. It may be necessary to apply a small amount of water around the rubber seal of the vacuum tester to make a good suction fit.
MQ41TDH — MAINTENANCE
5.Check and make sure that there are no air leaks between the vacuum tester and the inlet port on the pump. If air leaks are present reseat vacuum tester.
6.Run the pump for a few minutes while monitoring the vacuum guage. If the guage indicates a reading between
7.If the vacuum tester guage indicates a reading below
6.To test the flapper valve, shut down the engine. The vacuum tester should remain attached to the pump suction inlet port by vacuum. This indicates the pump's flapper valve is seating properly to hold water in the suction hose when the engine is stopped.This prevents backflow and allows for faster priming when the engine is restarted.
NOTE
25 in. Hg (inches of mecury) translates into 25 feet of lift at sea level.
MQ41TDH TRASH PUMP — PARTS & OPERATION MANUAL — REV. #3 (04/02/07) — PAGE 21