Multiquip MQD2H manual Maintenance, Pump Vacuum Test, FlapperValve Replacement

MAINTENANCE

Pump Vacuum Test

To perform the pump vacuum test do the following:

1.Start the engine as outlined in the initial start-up section, and wait for the pump to begin pumping.

2Check and make sure that there are no air leaks between the vacuum tester (Figure 21) and the inlet port on the pump. If air leaks are present reseat vacuum tester.

3.Run the pump for a few minutes while monitoring the vacuum gauge. If the gauge indicates a reading between -25 and -20 in. Hg. (inches of mercury) then it can be assumed that the pump is working correctly.

22 in. Hg (inches of mercury)

NOTE translates into 25 feet of lift at sea level.

FlapperValve Replacement

1.Remove the two bolts that secure the suction port chamber (Figure 20) to the pump well. Remove suction port chamber. Replace valves as required and reassemble.

4.If the vacuum tester gauge indicates a reading below -20 in. Hg, it can then be assumed that the pump is not functioning correctly, and corrective action needs to be taken.

5.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.

Figure 20. Flapper Valve Replacement

2.Remove the two bolts that secure the discharge port (Figure 20) to the pump well. Remove discharge port plate.Replace valves as required and reassemble.

Gear Reduction Oil (Transmission)

1.Check gearbox oil level every 20 hours of operation or at least once a week; more often if any leakage is detected around the gearbox.

2.Change transmission oil after the first 40 hours of operation. Use SAE 80/90 EP (API GL-5) gear oil. Transmission oil capacity is 22 ounces (651 ml.).Check oil level periodically and change oil after every 350 hours of operation.

Connecting Rod Bearing Lubrication

1.Grease connecting rod bearing (Figure 8) every 8 hours of operation.This is done by rotating the rod bearing to the 12 o'clock position. At this point the grease fitting will be visible through the guard hole.

2.Use only premium lithium based grease, conforming to NLG1 Grade #2 consistency.

3.Remove connecting rod guard occasionally and wipe up excess grease from connecting rod bearing.

PAGE 20 — MQD2H/3H DIAPHRAGM PUMPS — OPERATION AND PARTS MANUAL — REV. #6 (10/27/11)