cavitation and pump won't build pressure

Discussion in 'Pumps and Tanks Well Forum & Blog. Water is life.' started by red2.7, May 7, 2018.

  1. red2.7

    red2.7 New Member

    Joined:
    May 7, 2018
    Location:
    Ontario
    Hi out there
    I replaced my shallow well pump to get more pressure to a second floor shower. I bought a 3/4 hp 30/50
    red lion from home depot. It is connected to an expansion tank and a 10 ft deep well. The pressure switch closes and then the pump will run on and on and not build pressure. If I shut off the pump for a second or two and restart then, the pressure builds normally . Next time the pressure drops it's the same thing all over again. The pressure side of the pump has a priming port to which I installed a valve to bleed air out and prime but it still goes through the same cycle. Why would shutting off the pump momentarily "fix" the problem ? Anyone had a similar issue? It's spring and the water table is high.

    Thanks
    Wally
     
  2. valveman

    valveman Cary Austin Staff Member

    Joined:
    Mar 15, 2006
    Occupation:
    Pump Controls Technician
    Location:
    Lubbock, Texas
    Sounds like you have a suction leak. Probably right where plastic pipe screws to the pump.
     
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  4. Reach4

    Reach4 Well-Known Member

    Joined:
    Sep 25, 2013
    Location:
    IL
    red2.7, try searching this forum for sha ving (without the space) for a method of finding vacuum leaks.
     
  5. red2.7

    red2.7 New Member

    Joined:
    May 7, 2018
    Location:
    Ontario
    You were on the right track with a vacum leak. I re-sealed the threaded fittings and still had the same problem. So I switched from white sealant, cleaned the fittings and used tapeit was better so I knew I was on the right track. I took it all apart again and used tape and sealant and then it was ok.
    I did not like the pvc fittings much cause they would thread into the pump and check valve completely by hand. I could not find any 1 1/4 barb fittings in metal so just a ton of tape and sealant did the trick. Thanks for the advice. I will now tackle the other hundred chores around the house.


    Wally
     
    valveman likes this.
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