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Pump couplers

Dunc Member Posts: 1
I have five boiler feed pumps at various schools that are going thru couplers a two to three times a heating season. I have checked alignment, check valves & short cycling. The couplers are the model 4J rubber type. They are ripping in half. The teeth are fine. They all have older pumps next too them that work fine with the same coupler. Any one have any ideas?


  • Jeff Krawic
    Jeff Krawic Member Posts: 58

    This is a guess worth looking into. I'll bet you a nickel the motor mounts are showing signs of "sag" in the cradles if they have this type of mount. It is one of the most overlooked issues in pumps. Take a look at each end of the mounts and if there is a difference between the top thickness and the bottom thickness of the mounts then they need replacement. Sure do hope this helps!
  • flange
    flange Member Posts: 153

    i had a very similar issue three years ago. installed six new sewage ejectors, they were aligned, tested , ran great for about a week or two then they did the same thing. they were factory mounted with 5j couplings. tried the vendor, got no help, went to a drives specialty, counter man did the research for me and told me 5j was marginal for the setup, recommended going to a 6j. installed new coupling on one as a test, never again had a problem. once i made it go away, was able to get paid to repair all six.
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