problem emptying holding tank.

[DaveOnCudjoe]

specifically using the macerating pump for overboard discharge. As I continue to learn the systems of my 2012 R-25sc, I have discovered the macerater pump will not pump overboard. It sounds like the pump may not be priming. The boat has been unused for a while and I wonder if tank contents may have dried in the discharge port or the diverter valve. Suggestions on how to proceed would be appreciated.

 

[Mastercraft]

Sounds like a problem that I had ..... impeller in pump was bad

 

[Harry]

You might try back flushing through the external discharge port. Use your hose and pressure nozzle that fits snug in discharge port. Shoot water up the port several times without running pump. You might see old material run out. Next time shoot water up the port with pump running, This may take a few tries. If the pump primes you will definitely hear the change the pump is making and see the discharge .If you do get it pumping let it sit for a hour. If you come back and nothing you'll need to replace the pump. Impeller is damaged. Any air leak no matter how slight will cause pump to loose prime

 

[Harry]

I should have mentioned I did a thorough pump out of the holding tank prior to going through the steps above. I also had over a half full tank of clear water in the holding tank.