K4050 Retainer, O-rings, Seat

The water supply valves need not be shut off to make this repair but do NOT open the mixer valve until the repair is complete!

  • Remove long set screw - 2.5mm (3/32") hex key
  • Remove short set screw (if applicable) - 2.5mm (3/32") hex key
  • Pull spout straight up to remove - caution: water will drain from base of spout
  • Remove seat, O-rings and retainer - seat may have been left in faucet body
  • Clean spout and faucet body
  • Apply NSF-61 certified silicone (plumber's) grease to all grooves in spout base, inside surface of faucet body and inside surfaces of seat, O-rings and retainer.
  • Place seat, O-rings and retainer onto spout base as shown.
  • Apply silicone grease to outside surfaces of seat, O-rings and retainer.
  • Rotate spout until cross-hole in retainer is aligned with cross-hole in faucet body.
  • Lower spout into faucet body, without rotating, until fully seated.
  • VERY IMPORTANT- Use hex key to probe and verify cross-holes are aligned. Now you can rotate the spout while pressing with the hex key to 'feel' the hex key against the spout to confirm the holes are aligned.
  • Screw long set screw M5x0.8x7  into faucet body until seated against spout - CAUTION: set screw MUST pass through cross-hole in retainer and make contact with spout. Otherwise, water pressure will force the spout out of the faucet body when faucet is in use!
  • Rotate long set screw 1/2 turn counter-clockwise.
  • Screw short set screw M5x0.8x3 into faucet body (if applicable) until firmly seated against long set screw