Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 7 of 7

Thread: Pump Won't Prime; Draining Pool

  1. Back To Top    #1

    Pump Won't Prime; Draining Pool

    The hydrostatic value on my pool failed last week, and by the time I could get it repaired the pool was down to 4' of water in a a 9' deep pool. So, I decided to go ahead and replaster it, as its been 20 years. Replasterer cant come until next Monday, so I am circulating water through the pump and salt water cell to keep the water chemistry right. Monday I started the pump- main drain only as it was well below the skimmers, and it ran fine. Took about 5 minutes to prime, but no other issues. I noticed a leak around the main housing of my Hawyard superpump. so took it apart, and noticed the gasket on the diffuser was in bad shape, so replaced it, and the main housing gasket where the motor part of the pump meets the part that attaches to the debris basket. I also replaced the debris basket gasket. Used spa lube on everything. Reassembled everything, and now the pump will not prime. I've taken the following steps:
    (The skimmer valve is shut off)

    Used soapy water on the suction side valves and fittings with tea pump running to see if I had a leak.. Nothging apparent.
    inserted the garden hose into the debris basket and tried to fill the main dorian line, as there is alit of suction head that needs to be overcome , as the water surface level is now about 8 ' below the pump.
    Once it was full of water, closed off the basket lid and screwed it shut, turned pump on.. Water immediately drew down into the impeller, but then nothing happened in term of water flow.

    I tried repreating this procedure with the main drain valve closed, then slowly opening it to try to create a suction.. Nothing.
    Closed the main drain valve, and filled the skimmer lines up with water through the skimmers, and turned the pump on with the skimmer valve open to see if I could get it to prime with water from the skimmers. It did not draw down the skimmer level an inch. The only connections/ fittings on the suction side that I think could be leaking a re separated from each other on tea main drain and skimmer pipes, so one of tea two (skimmer or main drain prime) shield have worked if the connection fitting is leaking.
    In desperation, opened up the sand filter from the top and filled it with water to try to induce flow on the discharge side. Didn't work.
    I took the pump motor off, set it on its end and started it. The impeller is turning like crazy, humming along as it should.
    Putting a piece of paper against the external portion of the impeller, it is pushing air out.
    Disassembled the pump motor again, checked that the diffuser is in its proper location and there was no debris, etc anywhere.
    Back to the main drain only open, but tried it both with the air relief valve on the filter open and closed.. No luck either way

    So, I'm thinking there are 3 possible issues, understand that the pump was not designed to pull water 8' up into the air (Although it has done this all week- only difference now that I see is the pump was completely de-primed):
    There is a leak on th esuction side I can't find
    The impeller is moving but not pulling water.(Physically impossible??)
    There is some sort of air lock somewhere.

    I am out of ideas short of waiting till Monday to call a mechanic. Everywhere I have checked no one is available today, and are closed for the holiday the rest of the week.. But i need to have the pool drawn down by then for the plasterers to start work.... Any help. thoughts would be REALLY appreciated!
    31,000 concrete/ plaster pool built in 1980. sand filter, hayward superpump.

  2. Back To Top    #2
    Mod Squad zea3's Avatar
    Join Date
    Jul 2009
    Location
    Houston, Texas
    Posts
    9,201

    Re: Pump Won't Prime; Draining Pool

    If you can't get the pool pump to work you may be able to rent or buy a submersible pump to help empty the pool.
    TFP Moderator
    Helpful links: TF Test Kits,TFP Pool School, PoolMath
    Vogue 21' round AG, Pentair 1 hp 2 speed pump, 36 sq ft DE filter, Hayward S180T 150# sand filter, Houston, Texas
    Love TFP? Become a
    TFP Supporter!

  3. Back To Top    #3
    mas985's Avatar
    Join Date
    May 2007
    Location
    Pleasanton, CA
    Posts
    11,490

    Re: Pump Won't Prime; Draining Pool

    The suction lift on most pumps is around 8' so it isn't surprising you are having problems. Once it is primed, it is less of an issue although there is an extra 8' of suction head which can cause air leaks. You are better off with a submersible pump.
    Mark
    Hydraulics 101; Pump Ed 101; Pump/Pool Spreadsheets; Pump Run Time Study; DIY Acid Dosing; DIY Cover Roller
    18'x36' 20k plaster, MaxFlo SP2303VSP, Aqualogic PS8 SWCG, 420 sq-ft Cartridge, Solar, 6 jet spa, 1 HP jet pump, 400k BTU NG Heater

  4. Back To Top    #4

    Re: Pump Won't Prime; Draining Pool

    OK, i took off the impeller again and cleaned it, and made sure teh diffuser was seated better- it had come off. Would that keep it from priming? Now the pump runs for 5 minutes and shuts off for 15 or 20 then comes back on.
    31,000 concrete/ plaster pool built in 1980. sand filter, hayward superpump.

  5. Back To Top    #5
    mas985's Avatar
    Join Date
    May 2007
    Location
    Pleasanton, CA
    Posts
    11,490

    Re: Pump Won't Prime; Draining Pool

    Really, you shouldn't run the pump for 5 minutes without priming. The pump wasn't made to do what you are trying to do and you may have damaged it in the process. Heat can build up in the seal and motor which could be tripping the thermal limiter switch. There could also be an issue with the impeller causing the problem.
    Mark
    Hydraulics 101; Pump Ed 101; Pump/Pool Spreadsheets; Pump Run Time Study; DIY Acid Dosing; DIY Cover Roller
    18'x36' 20k plaster, MaxFlo SP2303VSP, Aqualogic PS8 SWCG, 420 sq-ft Cartridge, Solar, 6 jet spa, 1 HP jet pump, 400k BTU NG Heater

  6. Back To Top    #6

    Re: Pump Won't Prime; Draining Pool

    considerign i think the pump is at least 25 years old, rather than rebuilding it.. bearings are making noise and mechanical seals are leaking, wouldnt I just be better off buying a new pump?
    31,000 concrete/ plaster pool built in 1980. sand filter, hayward superpump.

  7. Back To Top    #7

    Join Date
    Jan 2013
    Location
    Sunnyvale, CA
    Posts
    108

    Re: Pump Won't Prime; Draining Pool

    Some Home Depo's rent sump pumps by the 1/2 day along with 25 or 50 foot hoses... worked for me.
    24k Gallon, Plastered in ground pool with attached spa
    Pentair 420 cartridge filter with 3HP variable speed Pentair 011018
    Solar panels
    EasyTouch8 with IC40 salt cell
    Aquabot Rapids 4WD

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •