Kenmore Dishwasher Not Cleaning Dishes: Spray Arms, Filter, Water Temp Fix

Common Symptoms

• Food particles remaining on plates, pots, or glasses after a full cycle
• White film or chalky residue on glassware (hard water buildup)
• Upper rack dishes dirty while lower rack dishes are clean (upper spray arm clogged)
• Gritty or sandy residue on dishes after cycle
• Detergent pod or powder still in dispenser at end of cycle (dispenser didn't open)
• Greasy film remaining on dishes despite full cycle
• Glasses coming out spotted or etched-looking

Most Likely Causes

1. 1

   Clogged Spray Arm Ports (Upper and Lower Arms)

   Spray arms distribute wash water across both racks through small jet ports. Mineral deposits (calcium, magnesium) and food debris progressively narrow or block these ports. When ports are partially blocked, water pressure drops and spray coverage becomes uneven. The upper rack is typically the first to show poor cleaning results because the upper spray arm depends on water pressure reaching it through the central tower. On 665.13743K605 and 665.12783K310, the lower spray arm attaches to a central post at the tub base; the upper arm clips or screws to a rear tower post at the back of the upper rack.

2. 2

   Clogged Manual Wash Filter (Whirlpool 665.xxx)

   Whirlpool-based Kenmore dishwashers including the 665.13743K605 and 665.12783K310 use a manual-clean filter system — a cylindrical fine mesh assembly in the sump floor that traps food particles and must be cleaned by hand every 1–3 months. When this filter is clogged with food debris, water flow to the pump is restricted, dramatically reducing wash performance across both racks. Unlike the self-cleaning (hard food disposer) models, the manual filter does not grind food — it catches everything. Check the filter first before investigating any other cause.

3. 3

   Insufficient Water Temperature

   Dishwasher detergent enzymes activate at 120–140°F. If incoming water is below 120°F, detergent doesn't fully dissolve or activate, and grease does not release from dishes. Kenmore dishwashers (both Whirlpool and Bosch platform) require incoming water at 120°F minimum. The water heater should be set to 120°F, and the hot water tap at the kitchen sink should be run for 60 seconds before starting the dishwasher to purge cold water sitting in the supply pipe. Both 665.13743K605 and 665.12783K310 have a built-in heating element that boosts water temperature during the wash phase, but they still need adequately hot incoming water to reach target wash temperature.

4. 4

   Stuck or Failed Detergent Dispenser Latch

   The detergent dispenser has a spring-loaded door that pops open during the main wash phase. If the latch tab is sticky (detergent residue), cracked, or blocked by a dish positioned in front of the dispenser, the detergent pod stays sealed and never contacts the wash water. On the 665.13743K605 and 665.12783K310, the dispenser is mounted on the door inner panel — confirm the door opens freely by hand before loading. The latch clip is a small plastic component that cracks with age; replacement dispenser assemblies are model-specific (~$20–$40).

5. 5

   Low Rinse Aid Level

   Rinse aid reduces water surface tension, causing water to sheet off dishes rather than bead and leave spots. An empty rinse aid reservoir results in spotted glasses, water marks on plastics, and dishes that don't dry effectively. On 665.13743K605 and 665.12783K310, the rinse aid reservoir is on the door inner panel adjacent to the detergent dispenser — fill it when the indicator window shows empty or the rinse aid light illuminates. In hard water areas, use the maximum rinse aid dosage setting.

6. 6

   Hard Water Mineral Buildup

   In areas with water hardness above 7 grains per gallon (120 mg/L), calcium and magnesium deposits coat the tub interior, spray arms, heating element, and filter housing over time. This buildup reduces spray arm port diameter, leaves white or chalky film on glassware, and makes the tub look dull and gray. A citric acid descale treatment dissolves mineral deposits from the entire interior without disassembly. Run a descale cycle monthly in hard water areas.

Quick DIY Checks

1. 1Step 1 — Clean the wash filter (665.13743K605 and 665.12783K310): remove the lower rack. Locate the cylindrical filter assembly in the center of the tub floor. Turn the upper cylindrical filter counterclockwise approximately 1/4 turn and lift it out. Below it, lift out the flat coarse mesh filter plate. Rinse both under warm running water, scrubbing with a soft toothbrush to clear food debris from the mesh. Do not use a wire brush — it will damage the fine mesh. Inspect the sump cavity beneath for glass fragments, food chunks, or debris that could jam the pump impeller — remove any items. Reinstall the flat plate first, then the cylinder (insert tabs aligned, turn clockwise to lock). Run a short cycle and observe cleaning results before investigating other causes.
2. 2Step 2 — Inspect and clean spray arm ports: remove the lower spray arm by pulling it straight up or unscrewing counterclockwise off its center post (model-dependent — 665.13743K605 lifts straight up; 665.12783K310 may unscrew). Hold the arm up to a light source and look through each port — clear open circles are normal; dark or narrowed ports are clogged. Use a toothpick or straightened paperclip to dislodge mineral deposits from each port. Rinse under the tap. For the upper spray arm: remove the upper rack and unclip or unscrew the arm from the rear tower post. Clean ports the same way. Reinstall both arms and confirm they spin freely with no wobble. A cracked spray arm loses pressure to ports and must be replaced.
3. 3Step 3 — Check water temperature: run the hot water tap at the kitchen sink for 60 seconds before starting the dishwasher — this flushes cold water from the supply pipe. For a temperature reading, start the dishwasher, let it run for 2–3 minutes through the initial fill phase, then quickly open the door and insert a cooking thermometer into the water at the tub bottom. Target: 120°F or higher. If below 120°F, check your water heater thermostat and set it to 120°F. On 665.13743K605 and 665.12783K310, if the heating element has failed (no temperature rise after the wash phase begins), an F-code may accompany the poor cleaning — check /fixes/kenmore-dishwasher-error-codes for the relevant code.

1. 4Step 4 — Test detergent dispenser latch: open the dishwasher door and manually open and close the detergent dispenser door 3–4 times — it should snap open easily and close with slight resistance. If the latch feels stiff or sticky, clean the area with a damp cloth to remove dried detergent. If the plastic latch tab is cracked or broken, replace the dispenser assembly (model-specific, ~$20–$40). Also confirm no dish in the lower rack is blocking the dispenser door from swinging open — this is a very common oversight.
2. 5Step 5 — Check rinse aid level: open the rinse aid reservoir cap (on the door panel next to the detergent dispenser). Inspect the indicator window — if it's empty or at the bottom, refill with liquid rinse aid. Rinse aid not only reduces spotting and film but also helps dishes dry without water marks. Set the dosage dial to the maximum setting if you're in a hard water area. After refilling, run a full cycle and assess the glassware — improvement is usually visible in the first cycle.
3. 6Step 6 — Citric acid descale for hard water buildup: with the dishwasher completely empty, add 1 cup of food-grade citric acid powder to the bottom of the tub. Do not add detergent. Run a full hot wash cycle. The citric acid dissolves calcium and magnesium deposits from the tub liner, spray arms, filter housing, and heating element. After the descale cycle, run one normal wash cycle with detergent and no dishes to flush residual citric acid before loading clean dishes. Repeat monthly in hard water areas.

Repair vs Replace

Recommended Tools & Parts

• Lower Spray Arm (Whirlpool 665.xxx compatible)

  Replacement lower spray arm for Kenmore 665.xxx dishwashers. Replace if ports are completely blocked or if the arm body is cracked. Verify model compatibility — 665.13743K605 and 665.12783K310 may use different arms.

  $15–$30

  Buy on Amazon →

• Detergent Dispenser Assembly

  Replacement detergent and rinse aid dispenser for Kenmore 665.xxx dishwashers. Replaces cracked latch or failed wax motor. Model-specific — include your full model number when ordering.

  $20–$45

  Buy on Amazon →

• Citric Acid Descaler (Food-Grade)

  Food-grade citric acid for dishwasher mineral deposit removal. Use 1 cup per descale cycle in empty dishwasher. Effective for hard water calcium and magnesium buildup on all Kenmore dishwasher models.

  $8–$15

  Buy on Amazon →

• Dishwasher Rinse Aid

  Liquid rinse aid for spot-free drying. Fill the reservoir inside the door panel. Use maximum dosage setting in hard water areas. Compatible with all Kenmore dishwashers.

  $5–$12

  Buy on Amazon →

Links are Amazon affiliate links (tag: fixitfastai-20). Prices are estimates.

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