KBI Turn off valve-Compression Seals?

Discussion in 'Irrigation' started by ed2hess, Feb 27, 2007.

  1. ed2hess

    ed2hess LawnSite Fanatic
    Posts: 13,140

    In one of my main lines I have a small leak at a kbi turnoff valve. This is a large diameter device with a 8" turning lever on top. It can be used to manually turn off water to one section. It appears that this device is glued to the 2" pipe on both ends. But, it looks like you could unscrew each end and remove the center part. I am not interested in removing the center part put maybe I could tighten it up and stop the leak. I would need an 10" pipe wrench to grip the thing. Is anyone familiar with this device? Someday I will learn to put photo up sorry.
     
  2. PurpHaze

    PurpHaze LawnSite Fanatic
    Posts: 5,496

    Without a better description/model of the valve, picture or URL showing exactly what it is one would only be hazarding a guess. When it comes to isolation valves there are just way too many types; butterfly, ball, gate, resilient wedge gate, etc.
     
  3. jerryrwm

    jerryrwm LawnSite Bronze Member
    Posts: 1,274

    Ed, that sounds like a true-union ball valve.

    http://www.aquamasters.com/trueunio.htm

    You need a good strap wrench or a 'chain-tong' wrench with a piece of hose on the chain to protect the union.
     
  4. NC_Irrigator

    NC_Irrigator LawnSite Bronze Member
    from NC
    Posts: 1,415

    if you can take the pressure off that valve you could probably tighten it by hand
     
  5. ed2hess

    ed2hess LawnSite Fanatic
    Posts: 13,140

    Yes sir Jerry that is exactly what I have....would it be a stupid idea to replace the valve body? The other alternative is to cut it out and put in coupler and forget the on/off. I dont really need this to be a a cut-off. I am thinking about how to rig a tool not clear on your two recommendations. When you say strap wrench are you talking about one of those rubber bands with a plastic handle..
     
  6. PurpHaze

    PurpHaze LawnSite Fanatic
    Posts: 5,496

    What size valve (line) are you talking about? Where exactly is the leak?
     
  7. Wet_Boots

    Wet_Boots LawnSite Fanatic
    Posts: 47,327

    Your giant slip-joint pliers can almost always deal with those union nuts.
     
  8. PurpHaze

    PurpHaze LawnSite Fanatic
    Posts: 5,496

    That's where I was progressing. However, if the ball valve is leaking through the seals in the handle stem (for his edification) this is not that rare in PVC ball valves. He should be able to turn the water off, use a set of large ChannelLocks to unscrew the unions and then just replace the valve. (We have ChannelLocks that will work on up to 3" PVC nuts.) If it's leaking at the union threads then he might get by just tightening them up after doping the threads with PVC approved pipe dope. If he doesn't know what he's doing though he could crack the PVC nuts. :)

    It's also possible that if the valve was under undue stress the PVC nuts could actually be cracked already. I've seen this occur when installers do not make sure that the soil under the ball valve is adequately compacted and then the whole thing settles over time.
     
  9. jerryrwm

    jerryrwm LawnSite Bronze Member
    Posts: 1,274

    No, I'm talking about a strap wrench that has a nylon web strap (kinda like a military or Boy Scout belt) attached to a metal handle. Chain tongs or chain wrench are the same principle but have a chain instead of the strap.

    http://www.ridgid.com/Tools/Specific-Purpose-Wrenches

    And those huge slip-joint adjustable pliers (Channel loks) can be used, but get the big pair. They also can be used as trot-line weights when you're not using them.

    As for replacing the valve body, you're gonna spend some bucks. Check the O-rings on the face of the seat. And like Hayes said, the valve could be a like under stress which makes a good union make-up difficult.
     
  10. ed2hess

    ed2hess LawnSite Fanatic
    Posts: 13,140

    Thanks for the help ....I am going to get after it soon.
     

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