4K5SSOB0 KitchenAid Mixer - Instructions

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

Used youtube movies to disassemble the mixer and found that the gear was stripped. I kept the screws in labeled ziploc baggies so I wouldn't forget which screws went where. Once the part arrived, it was very simple to replace the gear. I regreased the mixer and then reassembled. The trickiest part was how greasy everything was! It was also hard to get the pin through the beater hub - I found a video that suggested using a very slim screwdriver to thread the hole before inserting the pin. This was the most involved part replacement I've done on my own, and it was very satisfying to get my mixer back in working order!

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.

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

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

watched how to repair

I watched the university of YouTube videos, and followed their instructions.

Dismantled the mixer, took photos, and re-assembled unit.

Removed old one and replaced with new one.

line up the screw holes and screw it

Simple fix actually. UNPLUG mixer and remove the one screw on top that holds on the back. The Phase control board sits under and behind the paper insulator and "switch" assy. Remove the 4 wires with a pair of needle nose pliers, the one screw holding it to the back of the mixer and install the new one in reverse order.

No repair needed

The shield works sufficiently. Note that the shield is not a continuous circle as shown in the picture. This actually can be an asset because it can be installed or disassembled without stopping the mixer of having to lift the head while running.

changed the part

SO SIMPLE!!!!! Using a regular screwdriver, remove the remains of the Spring Latch. Place new one over holes and screw new one in place using the currently used screws. May wash off screws first if caked with gunk. OMG!!! TOOOO easy and saved me from throwing out a very terrific 40 year old PRO LINE KITCHEN AID MIXER!! To replace it would have been hundreds of dollars.