How To Fix Your KitchenAid Mixer
If you put too much flour in your mixer, it may bind and strip a very special gear actually made to be broken, in order to save the rest of the machine. Now I'm all for saving, especially these days. The great thing is that after pounding $350 into a mixer in more prosperous times (what were we thinking?) - this nylon gear can be found on-line for approx $10.00 plus shipping... Great value in doing this simple job.
Please note this is a "Classic" mixer, same process for either 4 1/2 or 5 quart, similar for tilt or stationary head. If you have an "artisan", it's different (as in new, improved, "all metal" and likely "toast" if you've read this far)... return that guy to Kitchenaid.
This mixer can be disassembled with a philips screwdriver, flat-head screwdriver, light hammer and a 3-pack of Stanley punches. Pictures are included to help walk you thru the process. I couldn't find much on the net myself, so I hope this helps.
Step One -This pic is the orbital piece located above the chrome ring, you know the ring which is approx. 5 inches in diameter (first pic above)? Gently catch the top edge of ring with the side of the flat-head screwdriver and tap the ring down. Remove the stainless "Kitchen Aid" branded strip with two (2) screws at the back. Next remove the mixer from the stand by removing the four big mondo screws (top pic). Now, if you look closely there is a pin visible on the recessed main shaft (denoted with red arrow, first pic above) which ties this orbital piece to the shaft (the main shaft, not the attachment). Firmly punch this pin just enough with a hammer and larger punch to get it moving, then progress to a smaller punch to push the pin completely out. Upon removal of this pin, gently work this (pictured) orbital piece down off the shaft. Caution, keep in mind it's aluminum... soft.
Doing so exposes five (5) screws in a circle, going through a ring gear. (I unnecessarily removed the ring gear in pic.) Remove these 5 screws and in addition, remove four others spaced such that they hold this pictured piece to the rounded top half of the mixer. Gently pry the halves apart being careful not to damage the thin black gasket. If pinched it's not a big deal as you can get a new gasket for $4. (Isn't this fun? Grandpa would be proud of you.)
Underside view of top half of mixer. Aside from the motor adjacent, this compartment houses the gear assembly. It wants to be cleaned of dark grease... leave the clean stuff. Then make sure you stuff in lots of new grease.