Noisy water pump

Faulty pressure switch perhaps? 

Or a leak somewhere in the system.

Or worn out pump. What type is it? Replacement seals are readily available.

peedee

Is it possible what you can see is the pressure switch rather than the pump? To save money some manufacturers are using internal submersible pumps. If that is the case the noise is coming from the pressure switch causing the pump to run too often to maintain pressure. There is an adjustment on the top which can be turned in either direction. How to do this should be detailed in the motorhome handbook.

David