4KSM90PSER0 KitchenAid Mixer - Instructions

I replaced the phase control board because the mixer had only
one speed and was surging. I noticed from other posts that it
is important to note the setting of the speed plate before you
remove it in order to remove the phase control board. Also be
careful removing the associated 'slip-on' terminals as it would
be easy to damage the speed plate. If I ever do this again I
will go ahead and replace the speed plate, probably the cheapest
item to replace. The operation was a success and the mixer is
back in business. Thanks.

I simply inserted the new beater into the mixer to see if it scraped the sides of the bowl. It fit perfectly and didn't scrape the bowl like the old one did.

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 is very straight forward. Remove the existing plate by removing the three phillip head screws. Use a regular screwdriver or knife to pop the plate off. (I cleaned the area while I was there but probably not necessary) Position the new plate with the screw holes lined up. Press down to pop the plate into position. Install original screws and tighten. You're done!

I watched a video on how to replace the worm gear. When I opened the mixer I noticed a small screw laying in the grease. I removed as much grease as I could and could not find anywhere that the screw would have come from. All the gears turned and looked fine so I replaced the grease put the mixer back together and it worked fine. I am thinking the small screw must have somehow fallen into the mixer when manufactured. So proud of my 70 year old self for getting the job done.

Followed your instructions from the internet and it was a simple fix. Mixer works great again. Thank You ..you made it easy!

had to replace the outlet strip and relocate the mounting screw,,,,wiring cord to the mixer was super correct and had to simply follow basic wiring (black to black,,,silver to silver,,,green to ground) ,,, the cord came with the correct mounting bushing already on the cord. Thx a bunch!

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.

Watched a couple of youtube videos and it was easy.

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.

disassembled replaced part reassembled now works well

I took apart the mixer housing and removed all the screws. The most difficult part was the two pins that needed to be removed with a metal punch. They were in fairly tight. The mixer came apart pretty easily and it was obvious which part needed to be replaced as it was broken and missing teeth. After replacing the gear and applying new grease for smooth operation, I simply put it back together and it has worked like new ever since.

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!

With the mixer being over 30 years old we believed it has going to have to be replaced. However, my husband jumped on uTube and looked at reviews for the problem. Motor was only running on high speed. Reviews said to replace the phase control board. Repair was very quick by just taking off the cover. Removing the old board and connecting the new. Mixer is working awesome once again. In such a disposable society it is great to be able to fix vs trash. Happy Baker.