5KSM125BCU4 KitchenAid Mixer - Instructions

Watched a couple of youtube videos and it was easy.

Followed instructions found onllne at Kitchenaid.com and replaced seals with parts obtained from PartSelect.

First i went to the Kitchen Aid web site and found a video on how to take a part the mixer. Followed the instructions from the video and it was very easy. The grease in the machine was black so i cleaned it out of the transmission and repack it with hi-heat wheel bearing grease that i got from a auto parts store it took about a 1/2 lb. then put the gasket in and back together and put the o-ring on. Have run for awhile and it is ok. Want to say that these are very well built machine.

Simply removed damaged gears. Very simple to do. Ordered gears. Replaced gears. Both working well ( so far. ) Machines are easy to dismantle. Just be sure to put the screws back in the holes you took them out of when dismantling...no lost screws. On the smaller model, took pictures of the wire positions to be sure they were replaced in the proper order. Larger model had no wires to remove.

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.

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

You tube has great instructions! I would suggest when you buy a part to let customer know that they need a food grade gear grease ordered to complete the reinstall of all gears and body parts!

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.

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!

Found control backplate out of adjustment. Should be nominal 3/8".Broken speed control spring which attaches to backplate bottom.
I recommend Loctite Blue to complement locknut's when adjusting RPM of "Stir" speed

I had a sourdough batch get into the space where dough hook attaches and it got so stuck that nothing - not hot water baths, not pliers and screwdrivers got the dough hook released. I had to open up the mixer following partselect you tube instructions and replacing the parts. What was confusing to me at first is that my 45 year old mixer had an extra screw on top of the shaft that no longer is there for newer models. It took me longer than I am willing to admit to figure that the extra screw is not the result of me skimming the instructions - the original shaft and dough hook went to a friend who broke it attempting to disengage the two parts (the dough turned out to be a very strong form of glue!). The piece is working like new. I preferred the agitator shaft with a spring to hold the end piece tighter, but the new set up without a spring works just fine.

The new part was too large for the replacement job, but we used the self tapping screws that came with the mixer and screwed them in from the bottom to open the holes a little more since the original screws were to short to hold the new plate. Then we replaced the screws with longer screws and that seemed to do the trick!

I watched a short video on replacing the worm gear, although I did not know what the problem was until I watched the video. after the video ended I took the mixer apart and found the problem located a parts number an placed my order. got the part in one week put in the new part in about 20 minutes and it work like new. and the price was very reasonable

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.

Repair went well after I figured out how to dis-assemble the mixer. Used straight & phillips screwdrivers and a small hammer & punch to drive out 3 pins. Ordered part# PS734233 pinion & shaft as shown in the parts page, it arrived on schedule, received part # 240210-2. Only problem was the new pinion had 10 teeth, the old/failed pinion had 11 teeth. Could not learn from anyone I called at PartsSelect or Whirlpool if the 10 tooth pinion was the correct part to use.
The teeth appeared to mesh with the mating gear,
installed the new pinion, reassembled and it worked fine. Not sure if it made a noticable difference in the output shaft speed.