How to Fix the Bonnet Nut Loosening on Kohler Coralais Faucets

The bonnet nut is the nut with a hole in the middle that keeps the faucet spout from sliding up and eventually coming loose.

If you have a single lever Kohler faucet and having an issue with the bonnet nut repeatedly coming loose, it may have been over-sprayed at the time of manufacturing and this article may apply to you.


  1. Image titled Kohlerhandle
    Remove the handle by popping off the small lid on the front and loosening a set screw with a 1/8" hex wrench.
  2. 2
    Remove the bonnet nut.
  3. 3
    Remove the spout by swiveling back and forth while lifting up with a steady, firm pull.
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    Chip away the over-spray with a small flat-head and a knife. Apply heat as needed.
  5. 5
    Wipe clean paint chippings from the inside
  6. 6
    Lubricate with plumbing silicone grease and reassemble.
  7. 7
    Optionally, use blue Loctite on handle set screw.


  • Wipe the bonnet clean with alcohol and wear a disposable rubber glove when tightening the bonnet back on for a better grip.


  • Don't scratch the parts of inside wall where o-rings sit on as this will cause a leak that you won't be able(or very difficult) to repair.
  • You must use a plumbing grease. The use of petroleum jelly will cause the o-rings to deteriorate and skipping lubrication may damage the o-rings during assembly.

Things You'll Need

  • 1/8" hex wrench
  • plumbing silicone grease
  • utility knife
  • assortment of small flat headed screw drivers

Article Info

Categories: Maintenance and Repair