4KSM150PSGN0 KitchenAid Mixer - Instructions

Went to partselect, found model number, printed blow-up of mixer. Figured out disassenbly procedure. Drove out main pin removing mixer head from stand. Save pin. Drove out pin in mixer main shaft which allowed planetary head to be removed. Save pin.
Removed stainless steel bezel to expose screws for removal of bottom half of mixer body. Removed screws and carefully separated mixer halves using two screwdrivers as prybars. Care must be exercised to prevent chipping of paint on body.
Separated body. cleaned grease from gears to find actual problem. Removed broken geartooth and grease near broken part to make sure no small broken chips remained. Removed pinion shaft assembly, drove pin from gear releasing broken pinion/shaft. Save pin/
Cleaned grease from pinion shaft assembly using mineral spirits and a small brush to reveal how part could be disassembled. Ordered part immediately on-line. Part arrived 1 business day after it was ordered.
Reversed process for replacing pinion shaft. Applied fresh grease obtained from excess already in mixer, spun pinion shaft to make sure grease was properly distributed. Reinstalled pinion shaft assembly. CAREFULLY plugged in mixer and jogged motor to make sure all was free and that mixer worked. If you can repair this mixer, you should have enough sense to do this diagonistic. Keep fingers away from all moving parts, don't touch expposed electric wires. Plug in only after making sure switch is in off position. Jog using mixer switch. Make sure mechanism is free.
Complete re-assembly by following blow-up and reversing disassembly steps. It may be good to write down you disassemblly procedure if it is possible that you won't be reassembling within a day or two.

INSTALLED PHASE CONTROL BOARD AND SPEED CONTROL PLATE, BOTH AT SAME TIME
Your DYI video was helpful, especially holding the spring with a cloth. Also good for fine tuning to get the speed exact

With a screw driver remove the screws holding the old base in place. With a flat head screw driver carefully pry and remove old mixer base. With 600 grit sandpaper clean and make smooth any burrs or rough spots in the mixer base recessed area. You can use some light grease and coat the outer edges of new mixer base and place in the now cleaned mixer base recessed area. The new base maybe a tight fit and not be fully seated in the recess. If a tight fit, place the piece of 2x4 piece of wood over the new part that is in the recess and carefully tap the base home using the sledge hammer. Check to see, if the base is fully seated. If not fully seated, tap again When fully seated replace the screws. You may have to adjust the height of the stand mixer head with mixer paddle attached for proper clearance between bowl and paddle. See your mixer manual for adjustment procedure

watched how to repair

Removed the rear cover to inspect the speed board. Replaced motor brushes and noticed the motor body nuts were loose and 1 was completely off. Cleaned up speed board and replaced the motor body nuts, tightened with nutdriver, adjusted speedboard governor screws and with new motor brushes worked like a charm. The very rough sounding motor noise was gone and the mixer has not operated so quietly ever.

Replaced gasket and O-ring. Problem solved. POC (Piece of Cake).

Took each area apart. Replaced the gear and reassembled it.

I watched a YouTube video all the way through, then watched each segment and followed along with the video. It was messier than the professional repair guy, but it worked out fine. This is not a difficult repair when you can watch a video and follow along. It saved me about $130.

Followed web site's videos. One step left out of video.

I did exactly what the PartSelect video demonstrated after watching other DIY videos on the Internet, thus I did not remove the stand which seemed like a little too much for a simple straight forward repair. This is the second time I have replaced this gear. The first time was about 10 years ago when the bakelite gear broke on a 30 year old KitchenAid K
-45. That mixer made hundreds of loaves of bread after grinding many pounds of wheat berries. The only reason we had to replace it was that it walked off the flour dusted counter and landed on its head when my wife had her back turned. Otherwise we would still be using it. :-)
Thanks for the excellent service and instructions.

replaced gear, and brushes.

Unscrewed the existing screw cap, put the new one in place, replaced the screws. So easy!

Got a harvest gold mixer from g maw and thought a project would be nice we have several of these mixers in the family i knew a 2 prong cord was not safe so i took apart the mixer and wanted to regrease it just give a lookie to see what i needed and then i decided after watching video on y tube to convert to a solid state.

Parts select as a whole has been very understanding as a whole and i will continue to get parts thru them they are genuine parts which is something i had to have i have 90% of my parts for a full overhaul we just cannot get the parts delivered fedex and usps i specify the address and they deliver 2 blocks east of the house thanks for honest neighbors usps was late as usual like i said parts select is outstanding at placing the order and appliances can be fixed super simple with the right tools the concern is with the fedex and usps now they are shorthanded but lets be real but when you deliver a package just triple check it is the right house !

I am not handy, but was able to follow this YouTube video and do this repair easily and successfully: https://www.youtube.com/watch?v=1QsgPIL9FpA

I did take the mixer apart first to verify that the worm gear was the issue, then ordered the part from you site. I received it quickly and was able to do the repair and get back to mixing in a few days!

Removed three screws and lifted out old part. replaced with new part