Need Help With Old Kohler Tub/Shower Valve Repair

Discussion in 'General Plumbing Help' started by Jeff Handy, Sep 12, 2019 at 4:16 AM.

Help Support Plumbing Forums by donating:

  1. Sep 12, 2019 at 4:16 AM #1

    Jeff Handy

    Jeff Handy

    Jeff Handy

    Well-Known Member

    Joined:
    Jul 5, 2019
    Messages:
    191
    Likes Received:
    35
    Location:
    Chicago suburbs
    Hi gang!

    So I was asked today to wade into fixing this dripping older Kohler tub/shower valve, by a neighbor of a looong time customer.
    I am guessing about 30 year old valve.

    I need to know current part numbers of the correct mixing cap and pressure balance unit.
    And any tips if anything to watch out for during replacement.

    They had hired a pro, who ordered parts twice, both times wrong, and then he gave up and quit.

    I know Kohler changes parts, makes old parts obsolete, re-designs, etc. I hate most Kohler stuff, too much crazy variety and poor designs.

    Pics are included of the valve body with the original pressure balance guts still installed.
    Also a pic with the original mixing cap still installed.

    There is a pic of the trim and handle, etc, if that narrows down the year or version of this valve.
    Sorry it is already removed.

    There were little springs and rubber boots between the mixing cap and pressure balance unit, similar to Delta junk, but longer springs.

    I also show pics of the two parts he left, the cap “might” be right, but I think only if the pressure balance unit current upgrade part is now way different.
    You can see on the back of the packages, one valve body pictured looks like the one here, with tabs on the sides, the other is round like a port hole.

    I think this valve body feeds from the back, sorry the pics don’t show supplies very well, and I was only over there a short while today.

    I have worked on some similar newer ornery Kohler valves that feed the sides of the valve body at 9 and 3, and the pressure balance unit has to be twisted in while trying not to carve up the seals. Like a meat slicer!
    I hope this is not that type.

    I did not remove the pressure balance guts today, once the parts on hand seemed mis-matched.
    Because everything is old and dry, and would likely leak, after re-assembly.

    Sorry for long-winded post, as usual!
     

    Attached Files:

  2. Sep 12, 2019 at 4:22 AM #2

    Jeff Handy

    Jeff Handy

    Jeff Handy

    Well-Known Member

    Joined:
    Jul 5, 2019
    Messages:
    191
    Likes Received:
    35
    Location:
    Chicago suburbs
    And yes, I closed the sink pop-up before laying out those little parts!
     
    Diehard likes this.
  3. Sep 12, 2019 at 5:51 AM #3

    breplum

    breplum

    breplum

    Professional Professional

    Joined:
    Nov 14, 2017
    Messages:
    229
    Likes Received:
    86
    Location:
    Lafayette, CA
    Hi Jeff,
    Certainly, the Kohler valve is K304 (confirmed by the pics on back of the card).
    The pressure balance spool looks right. And the part GP77759 is optional to replace when you want to update to smooth operation. It is universal and works with everything.

    K304 has been the basic valve body for many, many styles of trim.
    NEVER buy without the screwdriver stops, only with stops: K304KS
    They definitely have that very basic black plastic body, held in place with the four heavy stainless steel phillips type screws, and the stainless steel four hole securing plate.
    Looks like you have what you would need.
     
    GReynolds929 likes this.
  4. Sep 12, 2019 at 6:20 AM #4

    Jeff Handy

    Jeff Handy

    Jeff Handy

    Well-Known Member

    Joined:
    Jul 5, 2019
    Messages:
    191
    Likes Received:
    35
    Location:
    Chicago suburbs
    Thanks for the info!!

    I recognize the old valve body, but can’t pull the trigger on re-designed parts install until I am certain all is in place to button it up.

    This old mixing cap is held on by only two heavy phillips screws. At 9 and 3.
    And the new cap also only has two.

    My main concern is that the new mixing cap is totally incompatible with the old existing pressure balance unit.

    It looks like they eliminated the loose springs and Delta-style rubber boots.

    But the new cap will not at all mate with the old existing pressure balance unit.

    That is pbly fine, as long as the new pressure balance unit is a major re-design, totally new shape, but will fit and mate up with new cap design.

    Also, old pressure balance unit is a full disc shape, it fills up the whole recess of the valve.
    The new one is more like a narrow oval shape, lots of unfilled space above and below.
    And does the old disc shape part just wiggle out, is there a keyway, can I just yank with pliers?

    I just don’t want to yank out the existing pressure balance unit, then find that what parts I have won’t fix everything back up, at least leak free with the tub unused if necessary.

    Back of one package looks like right valve, with three tabs on each side, back of other package looks different.

    With Kohler weird parts, I have occasionally had to leave a client without house water, while I run around getting tech advice from Kohler or more parts from local supply house.
    All because some jerk cheaped out and did not spec the valve with stops.
     
  5. Sep 12, 2019 at 6:54 AM #5

    Jeff Handy

    Jeff Handy

    Jeff Handy

    Well-Known Member

    Joined:
    Jul 5, 2019
    Messages:
    191
    Likes Received:
    35
    Location:
    Chicago suburbs
    Ok, I just had a “Eureka moment”!

    It’s very possible that, when I removed the old mixing cap, the front part of it (with the springs) broke off, and stayed inside the valve.

    See my picture number 1.

    Now that loose fragment is blocking the view of what pbly is the existing oval shaped pressure balance unit.

    If this is right, everything else makes sense now.
     
  6. Sep 14, 2019 at 2:52 AM #6

    Jeff Handy

    Jeff Handy

    Jeff Handy

    Well-Known Member

    Joined:
    Jul 5, 2019
    Messages:
    191
    Likes Received:
    35
    Location:
    Chicago suburbs
    Update, all is well.

    Yes, the round black plastic part that you see in my first pic, was actually the front part of the old mixing cap.

    It separated and broke off, when the mixing cap was removed.
    It was really rocked in there pretty solid, from mineral deposits.

    When I pried that disc shaped fragment out, the normal oval shaped pressure balancing unit came fully into view.

    Then, I cleaned out the hardened mineral scale inside the valve body, dabbed plenty of silicone grease on all seals and rings, installed the new parts in my pics, and everything is groovy again.
     
    Last edited: Sep 14, 2019 at 3:04 AM
  7. Sep 15, 2019 at 7:38 PM #7

    breplum

    breplum

    breplum

    Professional Professional

    Joined:
    Nov 14, 2017
    Messages:
    229
    Likes Received:
    86
    Location:
    Lafayette, CA
    Thanks for the update Jeff.
     

Share This Page