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J pump cover (8-bolt) not coming free

Jack M
Jack M Member Posts: 223
Replacing the pump screen (annual maintenance) however, the gasket is really holding the cover on. The 8-bolts are removed but the cover will not budge. No silicon, just the paper gasket. What to do?


    EBEBRATT-Ed Member Posts: 13,760
    Tap it lightly with a hammer and use something thin to get it started if it won't break loose. Don't gouge up the surfaces though.
  • Jamie Hall
    Jamie Hall Member Posts: 21,517
    Or not so lightly... I've had pretty good luck with stuck gaskets with the sort of thin flexible spatula one uses for patching plaster. Get it just started in and tap it lightly. Much less chance of scarring the mating surfaces.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • Jack M
    Jack M Member Posts: 223
    edited September 16
    Should I crack this cast housing on the pump while tapping, will I be able to replace it?
    I will look around for a thin spatula (great idea).
  • STEVEusaPA
    STEVEusaPA Member Posts: 6,236
    Razor knife
    mattmia2Jack M
  • Too bad it doesn't have an exposed edge, otherwise you could use a slide hammer puller.
    8.33 lbs./gal. x 60 min./hr. x 20°ΔT = 10,000 BTU's/hour

    Two btu per sq ft for degree difference for a slab
    Jack M
    EBEBRATT-Ed Member Posts: 13,760
    @Jack M

    I am sure you can get a cover thousands of those made. The junk yards are probably full of old burners. And I am sur j pumps are still made. But you will get the old one off it's just stuck.
  • mattmia2
    mattmia2 Member Posts: 8,380
    This is gasketed joint 101.

    Slipping a razor blade in the joint works well for small things like this too.
  • 109A_5
    109A_5 Member Posts: 826
    Hello @Jack M,

    When my 50 year old McDonnell & Miller 67 LWCO needed some obvious maintenance (float chamber clean-out and float cleaning). I used the new paper gasket as a template for a new gasket made from silicone rubber sheet of similar thickness in hopes of avoiding the paper gasket woes in the future. So far so good, no leaks, have not dissembled it yet, it has only been about a year so far.

    Anyways, carefully tap with a hammer a utility knife blade held with narrow vice grips into the paper gasket to split the paper gasket. Put a bolt (or the like) back in a hole loosely so the cover can't fall.

    National - U.S. Gas Boiler 45+ Years Old
    Steam 300 SQ. FT. - EDR 347
    One Pipe System
    HVACNUT Member Posts: 5,247
    I definitely don't miss scraping stuck gaskets off the old pumps. Some guys would give up and double up on them.
    I used to (haven't seen a J pump in years) loosen all bolts then keep tapping the seam until it broke free. Then remove the bolts and start scraping.