Thumping Sump Pump

[JustAHomeowner]

Hello all,

I bought this house a few months ago. We’ve noticed the sump pump makes this odd, rhythmic, thumping sound every so often. It’s like a gulping sound, see video attached. It stops if you make it run. Any ideas?
In case this matters, pump flows to the lawn not sewer.

View attachment trim.DF69C099-222F-43BF-A792-54A324764470.MOV

 

[SHEPLMBR]

Open it up and check for debris in the pit. Or it could be airlocked. there should be a 1/4" hole drilled in pipe just a few inches above the adapter going into the pump.

 

[dmmsr]

Almost sounds like it is running with a little water in the pit. But I'm going to agree with sheplmbr. Could be airlock and need to drill a hole in the discharge line. Check to see what brand it is and check their specs on where to drill the hole.

When you open it and check it. See if it is running when it is making that noise. Zoeller m53 sump pumps were having trouble with their floats sticking. Normally they seemed to have trouble not turning on but did find a few that would stay running until you would shake the discharge. This was just a couple of years ago. We put a lot of them in for a long time until we kept getting recalls and switched to the m63s.

 

[mark3885]

Mine will sound like that when the float hangs up on the sump pit wall . Eventually it will drop, shutting off the pump . I pulled it out and put in a pedestal pump , no more noise and I have the submersible for a back up, if the pedestal goes south.

 

[Twowaxhack]

Sounds like the check valve bouncing as the discharge piping is siphoning itself.

 

[frontporch]

I second a check valve or foot valve based on the noise. Could it be that the pump is building up enough pressure to open that valve only to have it slam shut shortly after? I can’t say what the cause would be.

On the discharge pipe outside does it pump out water in spurts like an old hand operated well? I would examine it for a restriction in the pump bottom/screen