How to Clean Dishwasher Spray Arms (Step-by-Step Guide)

If your dishwasher is leaving food on plates, gritty residue in glasses or a film on cutlery, the spray arms are one of the first things worth checking. Blocked jets in the spray arms are a leading cause of poor washing results, and the good news is that cleaning them is a job most people can do at home in a few minutes.

This guide explains why spray arm jets get blocked, how to remove the top and bottom arms, the safe way to clear the holes, and how to refit everything so the arms spin properly again.

Why blocked spray arms cause poor washing

It helps to understand what happens inside the machine. When a dishwasher fills, it doesn't use fresh water constantly. It recirculates the same water for a long time during the wash. The motor pumps that water up and fires it out through the small jets in the spray arms, which is what scours your plates clean.

The problem starts when food hasn't been scraped or rinsed off properly before loading. That food gets into the dishwasher and is pushed around by the pump, and bits of it end up forcing their way out through the jets. Over time those small holes clog with food deposits, and once they're blocked the water can't reach everything in the basket.

Why the two end jets matter most

There are two jets at the very ends of each spray arm that do more than just clean. They're angled to make the arm spin. If one or both of these end jets are blocked, the arm stops turning and sits static. A spray arm that can't spin can only reach a small area, so most of the load comes out poorly washed. Keeping those end jets clear is the difference between an arm that whirls round and one that does nothing.

How to clean dishwasher spray arms

Most dishwashers have two spray arms: one below the bottom basket and another below the top basket. You'll want to clean both. Here's how to do it step by step.

Step 1: Remove the spray arms

Start by taking both arms out of the machine.

• Bottom spray arm: this is simply clipped into place. A small, firm pull straight up will release it.
• Top spray arm: this usually sits on a screw thread. Turn it a quarter turn and then pull it free.

Step 2: Flush and clear the jets

Take each arm over to the sink. First, run water through it and check that water flows freely along the central channel inside the arm. That tells you the main passage isn't blocked.

Next, work through each jet hole one at a time, picking out any blockages with something small such as a pin or a needle. This part can take a bit of patience and persistence, but it's worth being thorough so every hole is completely clear, including those two end jets that keep the arm spinning.

One important warning: do not try to make the jet holes any larger. The holes are sized to create the right water pressure. Enlarge them and you change that pressure, which can stop the arms spinning altogether.

Step 3: Refit the spray arms

With both arms clear, put them back in.

• Bottom spray arm: line it up and push down until it clips back into place.
• Top spray arm: offer it up and turn a quarter turn in the opposite direction to the way you removed it, until it locks on.

Give each arm a gentle spin by hand to make sure it turns freely before you close the door.

A quick reference

Spray arm	How it attaches	To remove	To refit
Bottom	Clipped into place	Small pull upwards	Push down until it clips in
Top	Usually a screw thread	Quarter turn, then pull free	Attach and quarter turn the opposite way

Keep results good for longer

A little prevention goes a long way. Scraping plates before loading keeps large food debris out of the machine, which means fewer deposits being fired through the jets in the first place. It's also worth checking the arms every so often as part of general maintenance, especially if you notice washing quality starting to slip.

Still getting poor results?

If you're experiencing poor washing, cleaning the spray arms is one of the most worthwhile things to try and it can make a real difference. But if results still aren't right after clearing the jets, something else may be at play, such as the filter, the pump or the water heating, and that's where a professional check pays off.

NAC engineers are fully trained across all major appliance brands and can diagnose and repair any make of dishwasher. We quote a service charge before an engineer attends, covering all labour, callout and VAT where applicable, and the only extra is for any parts needed, which we quote separately before any work goes ahead. Every repair comes with a guarantee under our terms and conditions.

You can book a repair quickly online or get in touch with our team. Prefer to talk it through? Call us on 0333 016 9622.

Looking for more home fixes? Browse our other guides, such as how to clear a blocked fridge drain hole and how to safely isolate an appliance before a DIY repair.