How To Repair Dishwashers/KitchenAid Repair/Chopper Replacement

Disassembly guide to access the chopper assembly in:
KitchenAid K series dishwasher (similar to Whirlpool and Kenmore models)
Model: KUDK03CTWH
Also works for model: Kenmore 655.15959000
Also works for models: KUDS03CTSS and KUDS301VBS3
Also works for model: KIDI02FR
The main differences were:

• Four instead of three torx screws to remove the filter unit
• A simpler chopper cover with one instead of two screws, and no 'hinged' flap
• The chopper has four blades instead of two.
• These models have the 'ProScrub' option, which means you have to pop the blue plastic ProScrub unit from the lower vertical section of the water conduit before trying to rotate the conduit 30 degrees clockwise.

Safety:
This disassembly exposes you to the chopper blades in this dishwasher. If the door safety interlock fails, the dishwasher could return to an active mode where these blades spin and would injure you. To be safe, remove power from the dishwasher before beginning this repair.

Goals:
Replace the chopper unit. If the chopper does not function, the adjacent mesh filter will clog, there will be poor water flow through the dishwasher, and the items on the top shelf will not be washed. You can put a glass right-side-up in the top shelf to see if there is water being supplied to the top washer/spinner. The chopper unit is easily destroyed by ingesting parts of a broken glass. This will shear off the stem of the shaft that drives the chopper blades. As noted below the chopper can sometimes be repaired by melting the end of the plastic shaft and pressing with a flat piece of metal to expand the end sufficiently to keep the blade and other chopper parts locked to the shaft.

Tools Required:
Torqx screwdriver
Slip-lock or vice-grip pliers

Part to be replaced:
"chopper assembly"
Part Number: AP3039186 made by WHIRLPOOL
see for instance http://fixitnow.com/, http://www.appliancepartspros.com/

1) At the start:

2) Remove clips in each of the top slider rails to allow removing the top basket. This is needed to make room to work and to remove the upper water conduit. There does not seem to be an easy way to remove the door, which would make this job easier. On some KitchenAid models it is difficult to remove/replace the slider rail clips as they do not have push-button release mechanisms. In this case you can leave the top rack in place and carefully work around it to remove the upper spray arm water conduit.

3) Everything is cleared out of the way, ready to remove the lower spray arm.

4) Remove the lower spray arm by un-screwing the center cap clockwise (yes this is the opposite of normal threading direction, the plug will go down and out the back of the spinner).

5) Both the fine filter (round 8") and the water conduit leading back and up to the top will need to be removed.

6) The water conduit has to be removed. It might be possible to take it apart, but the more direct approach is to release the back (here) clip, and the top clip.

7) A similar clip must be released at the top:

8) With the water conduit released from the clips, the whole assemble must be rotated thirty degrees clockwise about the central pump outlet. This will release this plastic item from its bayonet mount there so it can be removed.

9) Remove this thing. There's a flat nylon washer on the bottom. Don't lose it.

10) Remove first of three torqx screws to release the filter. The screws are at ten o'clock, eight o'clock and 4'clock. This is the eight o'clock screw.

11) Remove the second of three torqx screws to release the filter. This is the ten o'clock screw.

12) Remove the third of three torqx screws to release the filter. This is the four o'clock screw.

13) Remove the filter and base.

14) Top view of the exposed sump and chopper assembly (under the cover on the bottom left). Finely filtered water is drawn into the pump through the small inlet pipe at 5 o'clock. The pump output is in the center. There is a coarse filter formed by the slotted cover at 7 o'clock (and below) that passes water to the chopper unit. The details of the water flow are unclear to me, but apparently a large fraction of the water flows through the chopper; because blocking this severely reduces the water flow out through the pump.

15) Remove the first of two torqx screws in the top chopper cover. There is a second screw to the right side (at 6 o'clock in this photo).

16) Lift off the top cover. At this point the hemi-cylindrical inner cover should lift off, but I found it to be tightly wedged into its mounting flanges, and it would not move. The cover is "hinged" on the right hand side and should pivot from the left edge toward the check valve cover on the right. There is a tight friction fit of this cover with the sump. Perhaps by grasping under the bottom edge of the cover and right-hand-side tabs it could be broken free. I used 8 inch slip lock pliers to grasp the small tab on the top of the cover and wiggle it free. NOTE: There is a small recess on the screw side that is made to fit a screwdriver blade in to rotate the cover up. It's vertical, on the rounded part of the cover. Needlenose pliers can also be used to gently grasp the screw hole on the left side of the cover and then you can lift the cover out. This might be the only way to free a stuck cover if the tab is broken or too worn to be grasped with pliers.

17)The old chopper. If it is not broken, just clogged, clean the screen and replace. A clean chopper screen will make a surprisingly large difference in the water flow through the rotating arms.

18)The old chopper removed.To remove the old chopper, pull the blade towards the front of the machine and lift the screen up. If you are lucky and the shaft is not badly damaged, just the end cap is no longer holding, the chopper can be repaired by putting the components in place on the shaft and melting the end of the plastic shaft with a flame and then quickly pressing flat with a knife blade to expand the end and lock on the blade and washer etc. This is likely not a permanent fix so a new chopper should be ordered. It will get you back up and running in the short term.

19)The new chopper.

20)The new chopper installed. Note that it fits into the outer, narrower slot. To easily install the new chopper, grasp the screen and pull the blade away from it. This compresses the spring and prevents binding of the shaft when lowering the screen into place. Then insert a spacer (crescent wrench works well) between the blade and the screen. This keeps the shaft out of the way so you can lower the screen into its slot. Note the notches in the screen, the narrow side goes down. Once in place, remove the spacer and the shaft will snap into position.

21)Putting it back together. The "Thing" (above) goes in before the water conduit and should sit loosely. Do not press it down.

22)There is the correct water level.

Done.