Ron for Model Number 665.16824400 The lower arm has a grey plastic threaded cap screwed into the arm. I thought it was only a plug as it turns with the arm. It appears hard to get out as the top ears want to break.
Answer Hello Ron! You will need to hold down the wash arm WP8268874 and the sprayarm nut WP8268873 will unscrew from its location. Hope this helps! Read More... Answered by AppliancePartsPros.com | Wednesday, May 25, 2011