4KB25G1XGA5 KitchenAid Mixer - Instructions

Worm gear strips usually after the lower gear housing breaks. Tore down cleaned grease and shrapnel out, replace stripped worm gear and lower housing. It's convenient that the lower housing plate comes assembled with new bushing and gear. This is now the third one of these expensive mixers I have repaired, word got out that I fix them, and this is a very common problem. Repairs have been for friends and Church, so I don't charge any labor, it's kind of fun, messy, but fun. Note to Kitchen Aid: Please strengthen lower gear case.

removed the cover, separated the gear casing, cleaned the gears, replaced the thrust bearing kit and worm gear, greased all and reassembled. Wish I would have known to order the grease, it would have saved a couple bucks in shipping.

After trying to make a batch of heavy frosting, my KitchenAid mixer final stopped turning. After watching a video of how to change the grease in a similar model on PartsSelect and seeing it wasn't that hard to take apart, I decided to give it a try myself. Removing the cover exposed a completely worn gear drive. Luckily, it was easy to determine which parts needed replacing and PartSelect sent them in no time. Once I put everything back together, it sounded terrible which was pretty tough to take. As it turned out, the problem was flecks of metal from the gear were still in the grease and were getting caught in the mechanism. Once I thoroughly cleaned all the grease out and gave it some fresh grease the machine worked great. Much better than before. I only wish I had swapped the grease out at the same time. Thank you PartsSelect for saving me hundreds of dollars on a new machine!

You must have new bevel gear and can of food grade grease, ordered together. 1. Remove screw from back of mixer, holding the trim band; remove band. 2. Remove four screws holding the top cover. 3. Remover cover 4. Remove two screws holding the pc board and motor speed control; lift board out of the way. 5. Remove four screws holding gear cover; remove cover. 6. Remove as much gear grease as is accessible; discard. 7. Remove snap ring from vertical shaft holding bevel gear. 8. Remove horizontal shaft/gear by lifting straight up. 9. Remove bevel gear by sliding up shaft. 10. Remove cross pin holding lower gear. 11. Remove lower gear by sliding up shaft. 12. Remove vertical shaft and rotating head by tapping on top of shaft. 13. Clean all grease from gear case and on all gears (ground metal from bevel gear will be in this grease). 14. Clean all grease from inside gear cover. 15. Making certain gear case is now clean of all old grease, use putty knife to place grease in bottom of gear case. 16. Rub light coat of grease on vertical shaft and slide shaft back up into bottom housing. 17. Slide lower bearing back down vertical shaft. 18. Reinstall cross pin holding lower gear. 19. Place grease on lower gear. 20. Slide bevel gear down vertical shaft, making certain recess in underside of bevel gear lines up and sits completely over top of lower gear; when the bevel gear is fuly seated the snap ring groove will just be showing on the vertical shaft. 21. Reinstall snap ring. 22. Lightly grease shaft of both ends og horizontal shaft/gear; make certain ball bearing on front of shaft is also greased. 23. Slide ball bearing, spacer and bronze bushing on front of horizontal shaft. 24. Silde bronze bushing on opposite end of horizontal shaft (flange on bronze bushing is placed facing the gear). 25. Place assembled horizontal shaft/gear into lower gear housing. 26. Liberally grease all gears, 27. Replace gear cover, replace screws. 28. Replace pc board and motor speed control. 29. Plug mixer in and run on lowest speed for at least 10 minutes;increase speed until satisfied gears ar running smoothly. 30. Replace top cover and trim band. Bake something

Noticed worm gear was worn out, ordered the parts, it came very next day. On YouTube instructions were very easy to follow. Important point to remember,I washed the parts in water with chlorine in it. Retaking ring was tough to take out, as I did not have parrot beak plier, could not find it at Home Depot or Lows. Putting the retaining ring I used circular nut driver, to press it on the shaft to slide down by hammering it. While assembling follow the instruction step by step from the you tube. Machine works smoothly. Performing well. Thanks to part select, excellent web page, efficient delivery. I would recommend them to all.

After removing the single philips screw from the back of the unit, the metal band will come off. Under the band you will find 4 phillips screws. Remove them to get the cover off of the unit. Once open, access the gear box in front by removing the four philips screws holding the gear box cover down. Remove any old grease from the unit as there may be pieces of broken gear in the grease that will damage the new gears. I used a small plastic scraper, some paper towel, rubber gloves and q-tips to get all of the grease out. Try to make a note of how much grease you removed and from where, so that you can replace about that amount later and in the correct spots. To remove the bevel gear remove the split ring holding the bevel gear down on the vertical drive shaft. Once the ring is removed it will be easier to move the bevel gear, but I found that it was somewhat press fitted on the shaft and I needed to use some channel locks to gently rock it back and forth to get it moving up the shaft. I then, also, (since I was in there) replaced the worm gear underneath the bevel gear by tapping the retaining pin out of the hole above the worm gear and then tapping down on the vertical drive shaft with a hammer to push the planetary gear down and out of the unit. Once free, I then regreased the planetary and reinserted it in the holder taking care to align the gears on the shaft and the panetary housing. Then I tapped the worm gear all the way down to the base taking care to keep the recessed notch on the top of the worm gear parallel to the pin hole above it. Then I replace then pin and tapped the bevel gear down onto the top of the worm gear and replaced the split ring. Realigned all of the horizontal and vertical gears and then repacked the grease. Closed up the gear box and test ran the unit on low. THen closed up the rest of the unit in reverse of opening.

The transmission housing was cracked and one of the bearings was broken. I replaced both of them, but the mixer really didn't sound any better. So I replaced the gears in the transmission, and while that was better it still wasn't correct. I am going to replace the other bearing and the planetary shaft and see it that aligns everything a bit better. I believe the problem is the way the gear on the end of the motor shaft is working with the worm gear, the bearings are not keeping the correct spacing. Hopefully, the new one in the rear will fix the problem.

I had previously ordered several other gears after I found one of the worm gears stripped. After putting it all back together, the one major gear in the unit that I had not replaced because it looked fine, the bevel gear, also stripped. Learning experience: this is a unit worth several hundred dollars, so don't skimp on a $4 part. Once you work on this thing, you might as well spend a few bucks more and replace ALL the gears - even if they look like they are okay. Furthermore, if you only take 15 minutes to do this repair, as some on this site suggest, you are probably not cleaning the old grease carefully enough. Make sure you properly clean out the old grease to remove any metal from stripped gears, and use a good quality grease to re-pack the gear case.

Great experience. Reasonable cost. Quick delivery. Would certainly use PartSelect again

ordered the part and put in in with the help from the instant repairman

replaced Speed control board. less than 40.00 took ten minuets from the time I started until we were making cookies.

Open the package with the new screw and it looked like the screw was wider. I tried it to see if it goes in and as long as you screw it straight in, there was no problem.

I sent for a new thumb screw and screwed it in where it belongs and now I can use my other attachments.

the plastic covering the thumb screw cracked almost half way and lost the piece....so the new one is being used to replace this old one...very easy to install

Removing the cover of the mixers "guts", it was immediate evident the a major gear had lost a few of its "teeth". Parts Select clearly offered the required part of this $300 mixer for a favorable price. I was fully impressed that it arrived within 4 days or my ordering the part. I simply exchanged the damaged gear and restored the mixer to service and I'm fully impressed with the Parts Select Company for their swift response to my needs.