So my water pump has entered a new phase. It is a high performance jet pump that is about 4 years old. Every 20 minutes or so it turns off for an hour due to thermal limit, and while it is running there is a fairly low, simple harmonic rattle that sounds like a plastic part is banging around.  The sound is coming from inside the pump area, not the motor itself. Bad bearing? I don't know.

 

Does anyone have any thoughts on what this could be? Can it likely be fixed or am I looking at a new pump?

 

Thanks for any advice.

 

I can't get more than 5 years out of a jet pump where death seems to be from ants. But never had the thermal switch trip.  Do you have a pressure gauge?  Not sure what there is to be rattling in the pump. (?)  This time of year, underground water levels get low and jet pumps at/near the surface get a bit jinky.

Difficult to say from your description, it could be a large munber of things, restricted in flow to the water supply, partially blocked pipe/s either on inlet or outlet side. 

Suggest your local pumpman has a look, might need a strip down to see what the problem is - probably fixable if only 4 years old. 

After its thermal shut down and restart, is it still noisy? 

Is the jet installed in the pump or is it  a "down the hole" arrangement? 

Don’t forget that the water table is low to very low now

Just thinking on a bit further, unlikely low or intermittent flow would cause thermal shut down, noise could be the impeller touching the casing - overloading the motor which then shuts down as it should.

Just confirms my earlier comment, get Somchai, your local pump fix it man in. 

Possible causes are a worn/ broken impeller. Pump supply restriction (choked filter on inlet line?). Failed bearing. 

Unless you can get access to the inlet filter all these jobs need to be looked at by someone with a level of expertise as the pump will need to be removed and stripped down.