the dirt cup on my nes510 is a pain to empty, stuff gets stuck in the top and won't fall out.

Diagnosis

The Eureka Flash NES510 utilizes a cyclonic separation system where air spirals rapidly to fling debris into the lower bin. However, the "cone" or cyclonic chamber at the top of the dirt cup has narrow apertures and a tapered geometry that creates a bottleneck. When you vacuum up fine particulate matter—such as drywall dust, pet hair, or slightly damp debris—these particles cling to the interior walls of the upper chamber via static electricity or moisture, forming a "plug" that resists gravity. Because the release latch only opens the bottom door, the debris trapped in the upper conical section remains suspended. Over time, this buildup restricts airflow, leading to a noticeable drop in suction power and potentially causing the motor to run hotter than normal. You can confirm this is the issue if you empty the bin but still see a visible layer of grey or brown "cake" clinging to the plastic ribs inside the top half of the canister.

How to Fix It

To fully clear the cyclonic chamber and restore maximum airflow, follow these precise steps:

1. Power down the unit and remove the dirt cup from the main motor housing by pressing the release button and pulling the canister straight down.
2. Open the bottom release door as usual to dump the bulk of the debris into a trash bin.
3. Inspect the interior of the upper cone. If debris is clinging to the walls, do not shake the unit violently, as this can crack the plastic latches.
4. Take a long, thin, non-conductive tool—such as a plastic chopstick, a bamboo skewer, or the capped end of a plastic pen.
5. Insert the tool into the openings of the cyclonic cone. Gently scrape the interior walls from top to bottom, breaking up the packed "cake" of dust.
6. Turn the canister upside down and give it three firm taps against the side of the trash can to dislodge the loosened particles.
7. If the debris is damp, use a dry microfiber cloth wrapped around your tool to "wipe" the interior ribs of the cone until no visible residue remains.

If That Didn't Work

• Deep Wash the Canister: If the debris is oily or sticky, mechanical scraping isn't enough. Remove the filters and rinse the plastic dirt cup under lukewarm water using a mild dish soap. Use a bottle brush to scrub the interior of the cone. Ensure the canister is 100% bone-dry (at least 24 hours) before reinserting filters, as any moisture will instantly turn dust into mud.
• Filter Replacement: Check the pleated filter located above the cup. If the filter is saturated with fine dust, it creates backpressure that forces debris to stay trapped in the cone rather than flowing downward. Replace the filter if it cannot be tapped clean.
• Static Reduction: In very dry environments, static cling keeps dust adhered to the plastic. Lightly wiping the interior of the cone with a dryer sheet can reduce the electrostatic charge that attracts fine particles to the walls.
• Check the Seal: Inspect the rubber gasket where the cup meets the motor. If the seal is leaking, the cyclonic action is weakened, meaning debris isn't being "spun" down into the bin efficiently and instead accumulates at the top.

Heads Up

• Avoid vacuuming damp carpets or spills; the NES510 is not a wet-vac, and moisture will turn the upper chamber into a cement-like plug that is nearly impossible to remove.
• Empty the bin when it is only 2/3 full. Waiting until the "Max" line is reached increases the likelihood of debris packing into the upper cyclonic chamber.
• Never use metal wires or coat hangers to clear the cone, as you can scratch the interior plastic, creating "burrs" that will trap even more debris in the future.
• Periodically check the intake hose for clogs; a partial blockage in the hose often causes a pressure backup that contributes to debris sticking in the top of the cup.