Installing Bulkhead Tips

Discussion in 'Equipment, Lighting, Hardware, Aquarium Filtration' started by AZDesertRat, Jan 10, 2010.

  1. Engloid

    Engloid Well-Known Member VRJ Member

    Joined:
    Mar 26, 2010
    Messages:
    1,324
    Likes Received:
    34
    Location:
    Tennessee
    If "slightest movement" lets the nut back off, then it wasn't tight enough. I've been in nuclear plants, and they require antiseize LUBRICANT on flange bolts that they definitely don't want to come apart by accident. They are often subjected to vibrations for many years. That said, if the threads are plastic, and clean, there's not really any NEED for lubricant. I just like it because it allows me to get the same pressure on the rubber gasket with less turning pressure on the nut.
     
  2. Kbra

    Kbra Well-Known Member

    Joined:
    Dec 21, 2009
    Messages:
    1,415
    Likes Received:
    0
    Location:
    San Luis Obispo, CA
    I got a 2" bulkhead that won't stop leaking. I've seen talk of plumbers putty. Is that reef safe?
     
  3. AZDesertRat

    AZDesertRat Well-Known Member R2R Supporter R2R Excellence Award

    Joined:
    Feb 25, 2009
    Messages:
    5,020
    Likes Received:
    1,124
    Location:
    Phoenix AZ
    Where would you put the plumbers putty? You don't wan tanything on the gasket as it loses its ability to vulcanize to the glass and makes it scoot or slip away. The external threads do not do any sealing and are only used to attach the lock nut. If you have internal threaded bulkheads you could use some putty there but plumbers putty is pretty thick and dries out with time, you are better off with the Laco PVC thread lubricant sticks or even teflon tape or paste as all remain pliable over time.


    Have you cleaned up all the threads and smoothed out all the sealing surfaces like the face of the flange and nut and the grooves of the internal and external threads? I would start there if you have not already done so.
     
  4. Kbra

    Kbra Well-Known Member

    Joined:
    Dec 21, 2009
    Messages:
    1,415
    Likes Received:
    0
    Location:
    San Luis Obispo, CA
    Been trying to find that lasco stuff online. No luck...
     
  5. AZDesertRat

    AZDesertRat Well-Known Member R2R Supporter R2R Excellence Award

    Joined:
    Feb 25, 2009
    Messages:
    5,020
    Likes Received:
    1,124
    Location:
    Phoenix AZ
  6. Kbra

    Kbra Well-Known Member

    Joined:
    Dec 21, 2009
    Messages:
    1,415
    Likes Received:
    0
    Location:
    San Luis Obispo, CA
    Where are you saying to apply it again? Between the rubber gasket and the inner tank?
     
  7. AZDesertRat

    AZDesertRat Well-Known Member R2R Supporter R2R Excellence Award

    Joined:
    Feb 25, 2009
    Messages:
    5,020
    Likes Received:
    1,124
    Location:
    Phoenix AZ
    No, the gasket must be kept dry.
    You use the thread lubricants on the internal threads such as the standpipe or return nozzle and the connection to a pump or sump drain. Its not usually wise to use it on the lock nut threads since for one they provide no sealing ability and two it could help the nut work loose over time if you move things at all.
     
  8. Kbra

    Kbra Well-Known Member

    Joined:
    Dec 21, 2009
    Messages:
    1,415
    Likes Received:
    0
    Location:
    San Luis Obispo, CA
    Ok the problem is leakage past the gasket. Not the internal threads. Not sure what else to do. Lossened ans tightened twice...
     
  9. Engloid

    Engloid Well-Known Member VRJ Member

    Joined:
    Mar 26, 2010
    Messages:
    1,324
    Likes Received:
    34
    Location:
    Tennessee
    If this stuff is a type of pipe dope, its not supposed to be used on internal threads...just like teflon tape. It goes on the external threads. :)

    its not the "proper" thing to do, but I have put pipe dope on gaskets before. It can help seal up small imperfections on the sealing surfaces. I had to do it before where a sump had been drilled, patched, and had a less than great surface.

    My advice is to clean the bulkhead, inside and out, clean out the threads so friction doesn't impede your ability to get the nut tight, clean the gasket, and put it back on. A little pipe dope on the gasket shouldn't be needed, but shouldn't hurt either, providing its the food safe teflon stuff.
     
  10. AZDesertRat

    AZDesertRat Well-Known Member R2R Supporter R2R Excellence Award

    Joined:
    Feb 25, 2009
    Messages:
    5,020
    Likes Received:
    1,124
    Location:
    Phoenix AZ
    DO NOT USE PIPE DOPE!
    Read the tips in the link here:
    LASCO - Support Center (The "Do's and Don'ts" of Assembling Threaded Plastic Fittings)

    No tape and no dope, period. The Lasco and LaCo products are thread lubricants not sealants or dopes.

    A few questions, is the gasket placed on the flange side of the bulkhead, regardless if its inside the tank or outside the tank, it does not matter andshould always go on the flange side. Is the gasket new or at least soft and pliable if used? How snug is the bulkhead in the drilled hole, ie does it have side to side play that would limit the gaskets sealing surface area? Does the hole have any chips, cracks or rough edges? How tight are you snugging the nut, it should only be about 1/4 turn past hand tight, overtightening is as bad if not worse than not tight enough. Did you take the time to smooth out the flanges sealing surface imperfections? Do you see any evidence of hairline cracks that may not be obvious until the nut is tightened, this is more common than you think.
     
    Last edited: Aug 1, 2012
  11. Kbra

    Kbra Well-Known Member

    Joined:
    Dec 21, 2009
    Messages:
    1,415
    Likes Received:
    0
    Location:
    San Luis Obispo, CA
    I took the bulkhead off and inspected the gasket. It's installed correctly. In tank against flange but I found the gasket has imperfections in it and little lips, possibly from spinning against the tank whole. Regardless I need a new gasket... :mad:
     
  12. Engloid

    Engloid Well-Known Member VRJ Member

    Joined:
    Mar 26, 2010
    Messages:
    1,324
    Likes Received:
    34
    Location:
    Tennessee
    Unless its really badly damaged, a little of the white food safe teflon pipe dope will help it seal. Regardless of what others may tell you....I'm speaking from experience, and what works. 20+ yrs as journeyman pipefitter...and I know what works.

    Of course, a new gasket is optimal, but sometimes changing a gasket or having a perfect sealing surface are just not possible.
     
  13. Engloid

    Engloid Well-Known Member VRJ Member

    Joined:
    Mar 26, 2010
    Messages:
    1,324
    Likes Received:
    34
    Location:
    Tennessee
    Actually, that's not what it says. It says, "Don't wrap Teflon tape or Teflon paste or pipe dope to add bulk
    to or to lubricate the joint."

    Putting it on the threads would be using it as a lubricant (on threads). Putting dope on the gasket is using it as a sealer on the gasket. If you read the reasoning behind their logic, it makes sense. That said, even at a nuclear plant, they want you to use pipe dope or tape, even on the threads.
     
    b4tn likes this.
  14. Kbra

    Kbra Well-Known Member

    Joined:
    Dec 21, 2009
    Messages:
    1,415
    Likes Received:
    0
    Location:
    San Luis Obispo, CA
    Will the pipe dope last over time and also not effect the reef?
     
  15. AZDesertRat

    AZDesertRat Well-Known Member R2R Supporter R2R Excellence Award

    Joined:
    Feb 25, 2009
    Messages:
    5,020
    Likes Received:
    1,124
    Location:
    Phoenix AZ
    Nuclear plants are not using PVC pipe or soft rubber gaskets, there is a difference.

    Kbra, you choose your method. I am also speaking from 37+ years of experience installing pumps, valves and domestic water systems. The tape or dope is a crutch to prop up a problem, it does not solve the issue, only mask or delay it.
     
  16. Kbra

    Kbra Well-Known Member

    Joined:
    Dec 21, 2009
    Messages:
    1,415
    Likes Received:
    0
    Location:
    San Luis Obispo, CA
    I appreciate the help from both you guys especially as a fellow nuke guy but I'm just gonna get some new ones...
     
  17. Engloid

    Engloid Well-Known Member VRJ Member

    Joined:
    Mar 26, 2010
    Messages:
    1,324
    Likes Received:
    34
    Location:
    Tennessee
    Actually there is a lot of pvc and rubber gaskets in nuke plants, as well as all other plants I have worked in.

    I do agree that replacement is the best idea, but its not always going to fix the problem especially if the sealing surface is not smooth. In the end, a gasket is designed to seal imperfect surfaces, and there are limitations on how imperfect a surface can be with a given gasket material. Adding a sealant can extend that limit.

    If the surfaces are pretty smooth, and its possible to remove the fittings, clean it alll up (access) is good...then by all means, replacement is the best option.... but I'm sure that, in 37 years, you have run into situations where you had to make do with the parts you have on hand/available, time you had, money, etc.

    It may be possible to just get some rubber and cut a gasket, rather than buy a new bulkhead. I'm not sure about availability of replacement gaskets, but I would assume they are out there...just never needed one.
     
  18. tcp316

    tcp316 Member

    Joined:
    Jan 8, 2010
    Messages:
    22
    Likes Received:
    0
    Location:
    Swartz Creek, Michigan
    So with the Glass Holes overflow box, do you put the gasket on the outside of the tank wall not the inside? I installed my overflow box from Glass Holes and had a horrible time with it leaking. This was a year ago. I finally got the leak to stop but recently I noticed excessive salt creep and sure enough it is leaking again. A very small amount but I am going to have to fix it. When I do my next water change I am going to try to correct it. I can't quite remember how I put the gasket but I believe it is inside the tank not on the outside wall. The nut is inside the box. Any suggestions?
     
  19. Engloid

    Engloid Well-Known Member VRJ Member

    Joined:
    Mar 26, 2010
    Messages:
    1,324
    Likes Received:
    34
    Location:
    Tennessee
    I never put the gasket on the nut side, because it's not made to take the friction of the nut spinning on it. That said, if the gasket is in good shape, and the surface it's on is clean and smooth, it will seal well...regardless of whether it's on the inside or outside of the tank. In other words, you can put the bulkhead in from the inside of the tank, or outside, nut inside or outside...but just put the gasket on the flare side, not the nut side.

    I have used some "food grade" teflon pipe dope on the gaskets before, when I had sealing problems due to an imperfect gasket or surface.
     
  20. AZDesertRat

    AZDesertRat Well-Known Member R2R Supporter R2R Excellence Award

    Joined:
    Feb 25, 2009
    Messages:
    5,020
    Likes Received:
    1,124
    Location:
    Phoenix AZ
    The gasket ALWAYS goes on the flange side, regardless if it is inside or outside the tank, wetted or dry. It never goes on the nut side period. The reason is water travels around the threads and eventually leaks when it is on the nut side.
    I would have to see a photo or drawing on how the Glass Holes kit installs but it should still be on the flange side. If the overflow box fits snug against the tank then it may require two gaskets, one against the flange inside the box and the other between the box and the insid tank wall.
     

Share This Page

Loading...