If you're unsure of the current condition of the impeller change it out. I've been told by a mechanic to run the motor every once in awhile to keep the impeller wet and flexible and to prevent it from drying out.
Impeller should last at least about 5 years.----Are you using factory parts ??-----Running the motor dry at any time ?----Running in a test bucket the water should be 6" above the impeller.
