A Kenmore dishwasher not cleaning top rack loads, while the bottom rack comes out fine, almost always has a problem in the path that carries water to the upper spray arm, not in the pump or the detergent. Start with the cheapest checks: the upper arm may be blocked or unable to spin, the rack may be seated badly or overloaded, the filter may be clogged, or the water may be too cold. Work through them in order, and you will usually find the cause in under half an hour with no tools.
Why would only the top rack of a Kenmore dishwasher stay dirty?
Most Kenmore dishwashers wash in layers. A pump drives water to the lower spray arm directly, and the water for the upper rack travels further, through a tube or a coupling at the back of the tub, to reach the upper arm. Anything that weakens that journey shows up first in the top rack. A blocked arm, a loose water coupling, a rack that does not seat properly or a filter that restricts the flow will leave the top rack dirty while the lower rack looks fine.
That is useful, because it narrows the problem. If the whole load is dirty, the cause is probably upstream: the filter, the pump, the fill or the detergent. If only the top rack is dirty, you are dealing with the upper arm and its feed.
Is the upper spray arm blocked or stuck?
This is the most likely cause, and checking it takes two minutes. Open the door, slide the upper rack out and look at the arm.
- Spin it by hand. It should rotate freely with a light push. If it drags, wobbles or catches on something, a rack item or a broken support may be the cause.
- Look at the spray holes. Hard water scale, food bits and bits of label or glass can plug them. Clear each hole with a toothpick, never with a metal tool.
- Take the arm off if your model allows it. Many arms twist or snap off. Rinse it under hot water and shake out any debris trapped inside.
- Check for cracks. A cracked arm leaks water before the nozzles and sprays weakly.
- Refit it firmly so that it seats fully and turns smoothly.
Our guide to Kenmore UltraWash dishwasher maintenance covers how often to clean the arms and the filter.
Is the rack loaded or seated wrongly?
A load can block the arm even when the arm is fine. A tall platter in the top rack, a bowl placed upside down over the arm or a utensil sticking through the basket can stop the arm from turning. Look for anything that rests against the arm’s path, and rotate the arm by hand once the rack is loaded to make sure it still turns.
The rack itself matters. If it sits crooked on its rails or has been put back in the wrong position, the water coupling at the back may not line up, and water leaks out before it reaches the arm. Push the rack fully in on its rails, check that the wheels are on the track and that any adjustable rack is locked in a single position, not halfway between two.
Could the filter or the water be the cause?
Yes, and these affect the whole dishwasher but tend to reveal themselves in the top rack first, since it has the weakest water supply.
- The filter. A clogged filter restricts the circulation. Twist it out, rinse it and brush the mesh. If food debris is packed in, wipe the filter housing at the bottom of the tub.
- The water temperature. Cold water does not dissolve detergent or soften grease. Run the kitchen tap hot before you start the cycle.
- The water level. If the tub fills only partway, the pump may run short of water. Check the inlet screen and the supply valve under the sink.
- The detergent. Make sure the dispenser door opens and the powder or tablet is not stuck. Use a fresh product, since old powder clumps.
If the whole load is poorly cleaned, read our broader guide on a Kenmore dishwasher not cleaning well.
Does it matter which factory built your Kenmore dishwasher?
It can. Kenmore dishwashers come from more than one maker, with 665 models built by Whirlpool and 587 models by Frigidaire, and the upper arm and its feed are laid out differently. The arm may be fed by a tube along the back wall on one design and by a connector in the rack on another. Check the prefix on the tag inside the door, and read whether your Kenmore dishwasher is Whirlpool or Frigidaire built so you know which parts and procedures apply.
When should you call a technician?
Call when the arm turns freely, the holes are clear, the filter is clean and the top rack is still dirty, since the problem is then a cracked feed tube, a failed coupling or a weak pump. Call too if the dishwasher leaks, will not drain or stops mid-cycle. A drain problem is a different path, so read the 587 dishwasher not draining guide if water stays in the tub. Our Kenmore dishwasher repair technicians test the pump pressure and the water path in one visit. We are an independent repair company, not a factory service arm, and we will tell you when a repair is not worth doing. You can book a visit with your model number.
