How to Troubleshoot & Replace Whirlpool AP6010550 / WP67500-55 Center Shaft O Ring

Watched videos available on APP's website, then ordered all necessary parts. Once parts arrived, just followed the videos again, step-by-step, to repair the mixer. I am NOT a "handyman", but with APP as my resource, I did it. Mixer running great now. 

For most 20-year-old KitchenAid Blenders the grease packed inside begins to break down into UCK and oil which will drip through the old gaskets. After breaking down the case and removing all of the old grease and oil I cleaned all the gearing and shafts. I replaced the case gasket, the 2 shaft gaskets that the lower orbital gear slides up, and then the o-ring on the main shaft after everything was installed. I did a break-in run on med speed for one hour and then tapped the chrome ring off of the lower unit and flipped the blender over and checked the 9 mounting screws to make sure they were still tight. Reinstall the ring and the blender is ready for the next 20 years. The Kitchen Aid site as well as others will give you the parts diagrams, as do many other parts sites. It's good to have a copy for future reference. Here at Doc' Shop we use APPros parts on many of our jobs and have always had successful job outcomes. They have good pricing and FAST shipping. Good luck with your KitchenAid repairs as this is surely a DIY job. Doug 

I opened it and found the worm gear was worn and allowing it two jump and then jam the drive screw so I replaced it as well as new thrust bearing and of course new washers now it works however the next time I will replace all the gears and bushings and the gear case because it is much more noisy than before and other parts may be worn that are hurting alignment also it good to note that the screws appear to be Philips also accept a 2 square Robertson driver and this works better 

New O-ring and new gasket 

I replaced the hub gear and the gear that it meshes with. I also replaced the prong on the center shaft and did a re grease. The mixer is now running smooth and quiet. 

The main culprit of the mixer not working was the worm gear (as usual). Girlfriend was unaware of limiting the mixer's speed to 2 for bread doughs, so she wore out the worm gear. It was a family item passed down to her with zero maintenance, so it needed new gaskets, grease, o-rings, etc. anyways, so between a full re-grease and a new worm gear it runs great now. The linked video tutorials for each part were super helpful and appreciated! 

Opened housing removed old gasket and replaced with new one. Received replacement parts surprisingly fast. 

KitchenAid stand mixers are easy to work on (just make sure you have snap ring pliers). With the parts from Appliance Parts Pros, the job of swapping out the old worn parts were a simple task (after all of the old grease was removed!). Works like a charm now. 

After reviewing some YouTube videos I was able to take the mixer apart and confirm my diagnosis of a damaged worm gear. I had some grease leakage for several years, so while I had the unit apart I decided to replace the gasket and O ring. Once I got the parts I completed the replacement of the 3 parts and put the mixer back together. Works like a champ now!! 

Took gearing cover apart and removed old grease from all gears and then replace with new grease.