Sand pump will not turn or grinding sound

1, a threaded shaft and impeller pump connected to (generally trash pump threaded connection) with steering pump test debugging, reversing the loss or damage to the pump impeller member.
2, the electrical control part of the problem, just start steering pump uniform requirement, but suddenly reverse running, the card refuses to turn the pump and damage the parts (of impeller and pump shaft with a threaded connection).
1, the steering is not allowed with pump test, the test should be a separate motor or other drive steering, steering is consistent with the requirements of the pump, and then together with the pump installed.
2. Check the electrical control, and individually try to turn the motor running.