Whirlpool WDF520PADM – Not cleaning bottom rack Repair Guide

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Model: Whirlpool WDF520PADM
Brand: Whirlpool
Model Number: WDF520PADM

🔍 Problem Description

Clean lower spray arm; check food chopper; verify pump pressure

📋 What You’ll Need

  • Lower spray arm
  • Cleaning tools

    • 🔧 Step-by-Step Repair Instructions

      🔧 Step 1: Remove and clean lower spray arm

      1. Open the dishwasher door fully until it rests horizontally.
      2. Pull out the lower dish rack completely and set it aside on your counter or floor.
      3. Locate the lower spray arm assembly in the center bottom of the dishwasher tub, directly above the circular filter housing.
      4. Identify the spray arm hub cap – a white plastic circular piece approximately 2 inches in diameter at the center of the spray arm.
      5. Grip the hub cap firmly with your dominant hand and rotate it counterclockwise (lefty-loosey) approximately one-quarter turn until it releases from the threaded mount.
      6. Lift the hub cap straight up and off the spray arm assembly.
      7. Grasp the lower spray arm by its outer edges with both hands and lift it straight upward off the mounting post – it requires no twisting, just vertical removal.
      8. Hold the spray arm under running tap water and visually inspect all spray holes (there are 16 total holes on this model).
      9. Use a straightened paperclip or toothpick to clear any debris from each spray hole by inserting the tool and pushing through from the top side.
      10. Check the center mounting hole (approximately 0.75 inches diameter) for calcium buildup or food particles.
      11. Fill your kitchen sink with 2 inches of warm water mixed with 1 cup white vinegar.
      12. Submerge the spray arm in the vinegar solution for 15 minutes to dissolve mineral deposits.
      13. Rinse the spray arm thoroughly under running water.
      14. Shake the spray arm vigorously to remove water trapped inside – you should hear water sloshing and see it drain from the spray holes.
      15. Visually confirm all 16 spray holes are clear by holding the arm up to a light source.

      🛠️ Step 2: Check food chopper for blockages

      1. Open the dishwasher door fully and pull out the lower dish rack completely, setting it aside on your counter or floor.
      2. Locate the circular filter assembly in the center bottom of the tub – it’s approximately 5 inches in diameter with a cylindrical mesh screen protruding upward.
      3. Grip the cylindrical filter screen and rotate it counterclockwise one-quarter turn, then lift straight up to remove the entire filter assembly.
      4. Set the filter aside and look into the sump area – you’ll see a black plastic chopper blade assembly directly below where the filter was seated.
      5. Use a flashlight to illuminate the chopper area and inspect for visible debris like bone fragments, toothpicks, fruit pits, glass shards, or paper labels wrapped around the blade.
      6. Grasp any visible debris with needle-nose pliers (6-8 inch standard size) and pull straight up to remove. Discard debris in your trash.
      7. Place your fingers on the black chopper blade (which resembles a small propeller with 2-3 curved blades) and attempt to rotate it clockwise and counterclockwise. The blade should spin freely with slight resistance.
      8. If the blade doesn’t rotate or feels locked, insert a flathead screwdriver (1/4 inch width) between the blade and the housing wall to gently pry away any stuck items while rotating the blade with your other hand.
      9. Once debris is removed, spin the chopper blade 5-10 full rotations in both directions – it should move smoothly without grinding sounds or hard stops.
      10. Run your finger around the circular sump opening below the chopper blade, feeling for any small items lodged in the perimeter gaps.
      11. Remove any additional debris found, then spin the chopper blade once more to confirm free rotation.

      ⚙️ Step 3: Verify circulation pump pressure

      1. Locate the circulation pump housing on the left side of the dishwasher tub bottom, approximately 8 inches from the front edge – it’s a gray cylindrical component about 4 inches in diameter.
      2. Place a shallow pan or towels under the pump area to catch residual water (expect 1-2 cups).
      3. Remove the single 8mm hex-head bolt securing the pump cover, located at the top center of the pump housing.
      4. Lift the pump cover straight up and set it aside – you’ll see the impeller assembly underneath with 6 gray plastic blades arranged in a circular pattern.
      5. Rotate the impeller clockwise with your fingers – it should spin freely with no grinding sounds and complete at least 3 full rotations without stopping.
      6. Check for debris around the impeller base and remove any buildup using needle-nose pliers.
      7. Press down on the center of the impeller with your thumb using 10-15 pounds of pressure – it should have minimal vertical play (less than 1/16 inch movement).
      8. Reconnect power to the dishwasher at the breaker.
      9. Close the dishwasher door and select the “Normal Wash” cycle, then press Start.
      10. Open the door after 2 minutes (the cycle will pause automatically).
      11. Look at the lower spray arm mounted on the tub floor – water should be actively spraying from all spray holes with strong, consistent streams reaching 8-10 inches high.
      12. Feel the water temperature at the spray arm – it should be warm to hot (120-140°F range).
      13. Press Cancel to stop the cycle, then disconnect power again at the breaker.
      14. If water pressure was weak or absent, the circulation pump motor assembly (part W10782773) requires replacement – proceed to Step 4.
      15. If water pressure was strong and consistent, reinstall the pump cover, secure with the 8mm hex bolt, and proceed to Step 5.

      Step 4.

    1. If water pressure was strong and consistent, reinstall the pump cover, secure with the 8mm hex bolt, and proceed to Step 5.

    🔩 Step 4: Inspect spray arm holes

    1. Remove the lower spray arm by gripping it at the center hub and pulling straight up—it lifts off without tools.
    2. Hold the spray arm under a bright light source and look through each spray hole from the inside, counting a total of 16 holes around the perimeter.
    3. Insert a straightened paper clip or wire (0.035-inch diameter maximum) into each hole, pushing completely through to dislodge any food particles, mineral deposits, or debris.
    4. Run the spray arm under hot tap water while rotating it, watching water flow freely through all 16 holes—water should spray out in thin, uniform streams.
    5. Check the center hub opening (1.5-inch diameter) where the spray arm mounts, using your finger to feel for any obstructions or buildup.
    6. Pull out the upper dish rack completely and set it aside on your work surface.
    7. Locate the upper spray arm attached to the underside of the rack, secured by a single quarter-turn lock nut at the center.
    8. Rotate the lock nut counterclockwise one-quarter turn and pull the spray arm downward to remove it.
    9. Count the 24 spray holes on this arm—12 on top and 12 on bottom.
    10. Use the paper clip method from step 3, clearing all 24 holes individually by pushing the wire completely through each opening.
    11. Flush the upper spray arm under hot water, verifying water flows freely through all holes without deflection or blockage.
    12. Inspect the mounting stud on the rack (the 0.75-inch diameter post where the spray arm attaches) and wipe away any debris with a damp cloth.
    13. Reinstall the upper spray arm by pressing it onto the mounting stud and rotating the lock nut clockwise one-quarter turn until it stops—the arm should spin freely by hand with no wobble.

    đź“‹ Step 5: Replace spray arm or clean chopper as needed

    1. Locate the lower spray arm in the center bottom of the tub, directly above the round filter assembly.
    2. Grasp the spray arm hub (the raised center piece) and rotate it counterclockwise 1/4 turn until it releases from the mounting post.
    3. Lift the spray arm straight up and off the water feed tube, which is a white plastic post approximately 2 inches tall.
    4. Hold the spray arm under running tap water and use a straightened wire or toothpick to clear all 16 spray holes around the arm perimeter.
    5. Inspect the center hub opening for debris, remove any buildup with your fingers.
    6. Align the spray arm center hole over the water feed tube and press down until it seats completely.
    7. Rotate the spray arm clockwise 1/4 turn until you hear a click, confirming it has locked into position.
    8. Spin the spray arm by hand; it should rotate freely without wobbling or binding.
    9. Remove the lower spray arm following substeps 1-3 above.
    10. Lift the round filter cover (approximately 6 inches diameter) straight up from the tub floor.
    11. Remove the cylindrical fine mesh filter by pulling straight up.
    12. Locate the gray plastic chopper cover in the sump area at the very bottom, centered under where the filter sat.
    13. Twist the chopper cover counterclockwise and lift it out.
    14. You’ll see a black two-blade chopper assembly; remove it by lifting straight up off the motor shaft.
    15. Use needle-nose pliers to remove any food particles, labels, or debris wrapped around the blade shaft.
    16. Wipe the chopper housing cavity with a damp cloth to remove accumulated residue.
    17. Place the chopper back onto the motor shaft, aligning the flat side of the shaft with the flat side of the chopper opening.
    18. Replace the chopper cover and twist clockwise until it seats.
    19. Reinstall the cylindrical filter, filter cover, and spray arm in reverse order.

    đź›’ Recommended Products

    Here are the recommended products for this repair: