Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 13 of 13

Thread: Pulsating Pump-Possible Leak?

  1. Back To Top    #1

    Pulsating Pump-Possible Leak?

    Here is my problem: When my pool is running from the skimmer, the pump seems to be running fine; a few air bubbles at the pump lid. The pressure holds pretty steady at 12-13 P.S.I. and the suction feels like it's normal. When I attach the Hayward Pool Vac to the skimmer inlet the pump just pulsates/chugs and the pressure varies wildly from 2-5 P.S.I. and the Vac is barely moving.

    Things I've done so far:
    1. Took the Sta-Rite 1 hp motor off, checked the impeller. Looks fine.
    2. Lube the Pump lid O-ring. (Could be an invisible crack on lid)
    3. Snaked the inlet pipe for debris. Seems clear.
    4. Closed off the skimmer inlet; filled pump inlet with water. No air bubbles observed and pump filled with water so hopefully the inlet pipe isn't leaking.
    (Note: my main drain is blocked and inoperable in order for the pool vac to work properly-old style pool with one diverter valve in the skimmer).
    5. Checked the Pool Vac/hoses- seem fine, no obstructions.

    I'm kind of at a loss as to what the problem is. Is it the pump inlet pipe/fittings that have a small leak causing this. That's my only guess right now.
    Any help would be appreciated.
    Thanks
    Jon W.

    20'x40' Inground, 42,000 gallons, gun-nite, 1hp Haywood Pump, sand filter, in-line chlorineator

  2. Back To Top    #2
    Richard320's Avatar
    Join Date
    Jan 2010
    Location
    San Dimas, CA (LA County)
    Posts
    18,768

    Re: Pulsating Pump-Possible Leak?

    Sounds normal to me... I don't know whether it's good or bad, but my pump starves when I hook up the vacuum. Face it, sucking 5' through 2" pipe is lots easier than sucking through 35' of 1¼" hose and 5' of 2" pipe.
    16K freeform gunite with spa; Pentair 4000 DE filter; Century Whisperflow 1 HP; Pentair Minimax heater.
    Troublefree does not mean Maintenancefree. It's like brushing your teeth: You can spend a couple minutes a day and pennies a week or go to the dentist once a year and spend several thousand dollars.
    A pool is like a pet - you have to feed it every day, even the days you don't want to play with it!

  3. Back To Top    #3

    Re: Pulsating Pump-Possible Leak?

    Actually I think the inlet is 1-1/2" and runs about 10' from skimmer to pump. Not that it matters.
    This hasn't done this before with the Pool Vac attached, so I know that this isn't normal.
    My local pool service will be out Monday to take a look at it.
    Jon W.

    20'x40' Inground, 42,000 gallons, gun-nite, 1hp Haywood Pump, sand filter, in-line chlorineator

  4. Back To Top    #4
    Mod Squad Bama Rambler's Avatar
    Join Date
    Jun 2009
    Location
    SouthWest Alabama
    Posts
    22,347

    Re: Pulsating Pump-Possible Leak?

    It's most probably an air leak. You can run a water hose over the suction side of the pump and plumbing while it's running and if the air bubbles go away you've found you're leak.
    Dave J. TFP Moderator
    24' x 52" Round AGP. 2hp/hp SPL Power-Flo 2-speed pump. 200sqft Waterway Cartridge Filter. 45MHP2(3GPD) Stenner Peristaltic Pump
    Pool School ----- Pool Math ----- TF-Test Kit

  5. Back To Top    #5

    Re: Pulsating Pump-Possible Leak?

    Dave J,
    Yep I did that this morning. No luck. Like I said, this only seems to be a problem when the Pool Vac is hooked up. I have even taken just a few hoses and connected them to the skimmer-no change, the pump pulsates intermittently like it has air in the system. I'm kind of at a loss here.
    Jon W.

    20'x40' Inground, 42,000 gallons, gun-nite, 1hp Haywood Pump, sand filter, in-line chlorineator

  6. Back To Top    #6
    cubbybeave08's Avatar
    Join Date
    Feb 2008
    Location
    Northwest Indiana
    Posts
    890

    Re: Pulsating Pump-Possible Leak?

    Quote Originally Posted by NCRhodes
    Dave J,
    Yep I did that this morning. No luck. Like I said, this only seems to be a problem when the Pool Vac is hooked up. I have even taken just a few hoses and connected them to the skimmer-no change, the pump pulsates intermittently like it has air in the system. I'm kind of at a loss here.
    When you attach the pool vac to the skimmer does the attachment fit right. Could it be getting air when you attached it?
    Beave
    Aqua Leader 24ft Round AG Wil-Bar Influence w/54 inch walls 13,500 gallons
    Swimline J-Blue Opal Liner, 1 4X20 Fafco Solar Bear Solar Heater
    Hayward 2 HP Swim Pro Voyager Pump Micro 150 with 4 way timer
    Swim Pro Voyager Filtration System with Hayward ABS Pearl wide mouth skimmer

  7. Back To Top    #7

    Re: Pulsating Pump-Possible Leak?

    Quote Originally Posted by cubbybeave08
    Quote Originally Posted by NCRhodes
    Dave J,
    Yep I did that this morning. No luck. Like I said, this only seems to be a problem when the Pool Vac is hooked up. I have even taken just a few hoses and connected them to the skimmer-no change, the pump pulsates intermittently like it has air in the system. I'm kind of at a loss here.
    When you attach the pool vac to the skimmer does the attachment fit right. Could it be getting air when you attached it?
    There might be a small amount of air when attaching it to the skimmer, but normally will 'clear out' and start suctioning properly after a few seconds.
    Jon W.

    20'x40' Inground, 42,000 gallons, gun-nite, 1hp Haywood Pump, sand filter, in-line chlorineator

  8. Back To Top    #8
    cubbybeave08's Avatar
    Join Date
    Feb 2008
    Location
    Northwest Indiana
    Posts
    890

    Re: Pulsating Pump-Possible Leak?

    Quote Originally Posted by NCRhodes
    Quote Originally Posted by cubbybeave08
    Quote Originally Posted by NCRhodes
    Dave J,
    Yep I did that this morning. No luck. Like I said, this only seems to be a problem when the Pool Vac is hooked up. I have even taken just a few hoses and connected them to the skimmer-no change, the pump pulsates intermittently like it has air in the system. I'm kind of at a loss here.
    When you attach the pool vac to the skimmer does the attachment fit right. Could it be getting air when you attached it?
    There might be a small amount of air when attaching it to the skimmer, but normally will 'clear out' and start suctioning properly after a few seconds.

    NC...I have a 2 HP pump and my auto cleaner does that...In fact usually what happens is that when I put it in the skimmer it will almost completely drain the pump basket than it reprimes, but after that it only primes up to just below the plastic window...never fully primes while running. I don't think mine ever fully primed again.
    Beave
    Aqua Leader 24ft Round AG Wil-Bar Influence w/54 inch walls 13,500 gallons
    Swimline J-Blue Opal Liner, 1 4X20 Fafco Solar Bear Solar Heater
    Hayward 2 HP Swim Pro Voyager Pump Micro 150 with 4 way timer
    Swim Pro Voyager Filtration System with Hayward ABS Pearl wide mouth skimmer

  9. Back To Top    #9

    Re: Pulsating Pump-Possible Leak?

    Just to update: my neighbor came over and we replaced the pipe, elbows, and new union from the pump to the 1st elbow underground that leads to the skimmer and letting everything dry for awhile. The straight piece of vertical pipe that goes underground basically came right off the joint. This PVC pipe was the thinnest walled stuff I've ever seen. Probably 35 year old pipe, elbows and glue (what's left of any).........in other words good places for an air leak. I'll let this dry and try tomorrow, but I'm afraid there is probably a leak elsewhere like the skimmer box or the pipe itself. Since the main drain is blocked off, there could even be an air leak at the pipe from the main drain to the skimmer box (tee).
    Jon W.

    20'x40' Inground, 42,000 gallons, gun-nite, 1hp Haywood Pump, sand filter, in-line chlorineator

  10. Back To Top    #10

    Re: Pulsating Pump-Possible Leak?

    Another update on this problem:
    I set up a temporary 1-1/2" PVC suction line from the pump to the pool (pipe layed above ground) to see if I can eliminate the air in the pump. I replaced the pump lid o-ring as well as the the pump drain plug o-ring on the suction side. Still no luck.. air in the pump. Had a pool tech with 30 yrs. experience come out to look at it; tested the the temporary suction line - no leaks, said, "I'm stumped". If anybody else has any suggestions as to what this problem could be I'd appreciate it.
    Jon W.

    20'x40' Inground, 42,000 gallons, gun-nite, 1hp Haywood Pump, sand filter, in-line chlorineator

  11. Back To Top    #11
    Mod Squad Bama Rambler's Avatar
    Join Date
    Jun 2009
    Location
    SouthWest Alabama
    Posts
    22,347

    Re: Pulsating Pump-Possible Leak?

    Have you resealed the drain plug(s) on the pump? There may be more than one.
    Dave J. TFP Moderator
    24' x 52" Round AGP. 2hp/hp SPL Power-Flo 2-speed pump. 200sqft Waterway Cartridge Filter. 45MHP2(3GPD) Stenner Peristaltic Pump
    Pool School ----- Pool Math ----- TF-Test Kit

  12. Back To Top    #12

    Re: Pulsating Pump-Possible Leak?

    Yep, there's two. Done that already.
    Jon W.

    20'x40' Inground, 42,000 gallons, gun-nite, 1hp Haywood Pump, sand filter, in-line chlorineator

  13. Back To Top    #13
    Mod Squad Bama Rambler's Avatar
    Join Date
    Jun 2009
    Location
    SouthWest Alabama
    Posts
    22,347

    Re: Pulsating Pump-Possible Leak?

    Have you ran water over everything on the suction side wheil it's pulsating?
    Dave J. TFP Moderator
    24' x 52" Round AGP. 2hp/hp SPL Power-Flo 2-speed pump. 200sqft Waterway Cartridge Filter. 45MHP2(3GPD) Stenner Peristaltic Pump
    Pool School ----- Pool Math ----- TF-Test Kit

Posting Permissions

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