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Almot's avatar
Almot
Explorer III
Mar 05, 2015

Flojet freshwater pump - faulty membrane?

Flojet model 03526144.
After several months storage it doesn't work anymore - motor is running, water isn't flowing.
Intake hose is not obstructed - I disconnected the hose and could suck the water right from the tank.
Out hose is not obstructed - I disconnected it and there is still nothing coming out.

If this is of any help - from the day one this pump didn't want to stop with faucets shut off, even though according to the specs it has a pressure switch, i.e. it should've stopped with faucets shut.

Dead membrane? And if so, - is it repairable/replaceable or should I just go online with my $80, buy a new pump and keep Shanghai factory happy? I don't feel that factory guys deserve much happiness in this case, considering a dead pump after 3 seasons of VERY moderate use.

10 Replies

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  • Almot's avatar
    Almot
    Explorer III
    Mar 05, 2015
    jrnymn7 wrote:
    Almot said,

    "If this is of any help - from the day one this pump didn't want to stop with faucets shut off, even though according to the specs it has a pressure switch, i.e. it should've stopped with faucets shut."

    How long after? It is normal for the pump to continue for a bit, in order to build the pressure back up.

    up to 10-15 seconds maybe. I didn't try running it "dry" for longer.
  • jrnymn7's avatar
    jrnymn7
    Explorer
    Mar 05, 2015
    Almot said,

    "If this is of any help - from the day one this pump didn't want to stop with faucets shut off, even though according to the specs it has a pressure switch, i.e. it should've stopped with faucets shut."

    How long after? It is normal for the pump to continue for a bit, in order to build the pressure back up.
  • jrnymn7's avatar
    jrnymn7
    Explorer
    Mar 05, 2015
    Could be debris, could be air, and could be scale.

    I run vinegar and water throughout my system before closing up for the winter... helps de-scale the hot water tank, lines, and pump.

    You can buy garden hose washers with a screen built in, to keep debris out of the tank, initially:

    medium sized mesh

    or one of these:

    very fine mesh



    and filter/strainers similar to the one posted above, by burbman, in between tank and pump.
  • BurbMan's avatar
    BurbMan
    Explorer II
    Mar 05, 2015
    I have a strainer on the inlet side of the pump that looks like this(yours may be threaded on both sides):



    The plastic bowl cracked over the winter and even though the crack was small, it allowed the pump to suck air and not water. Replacement was about $10, everyone carries them.
  • KJINTF's avatar
    KJINTF
    Explorer
    Mar 05, 2015
    Many newer rigs have a two position valve between the freshwater tank and the pump assembly. The "winterizing tube" is attached to this valve which selects between the tank or the tube. The tube is dropped into a jug of antifreeze saving dumping gallons into the freshwater tank.
  • Almot's avatar
    Almot
    Explorer III
    Mar 05, 2015
    Learning something new all the time. What do you call a "winterizing tube", and how do you turn the valve to winterizing mode? Not that I see any valve in my rig, other than kitchen sink faucets :)
  • wnjj's avatar
    wnjj
    Explorer II
    Mar 05, 2015
    Our Flojet pump also doesn't move water on its own. After it sits a long time or after travel I have to manually prime it. I've taken it apart a few times and the diaphragm is soft, clean and intact. I pull water into the winterizing tube by sucking on the hose with the valve turned 1/2 way. Then I turn on the pump and move the valve to winterize mode. It chugs for a second then starts to pump and that's when I switch the valve back to the tank.

    I don't remember for sure when this started but finding it running continuously for days or weeks after I left it on with an almost-empty tank sure didn't help.
  • ScottG's avatar
    ScottG
    Nomad
    Mar 05, 2015
    It could have sucked up something after the tank was refilled after being somewhat dry.
    My present TT did it after I had run a few tanks through it.
  • Almot's avatar
    Almot
    Explorer III
    Mar 05, 2015
    Will try rinsing it, thanks. What puzzles me is that it worked until it went to storage. So any debris would have appeared there when it was sitting idly.
  • ScottG's avatar
    ScottG
    Nomad
    Mar 05, 2015
    More likely it just has some small piece of debris in the rubber diaphragm. I have fixed a couple of these by simply dissembling the head and rinsing the parts off under water.

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