How to use a Kärcher wash brush
Updated: 21.10.2026
The brush only helps if it is seated, the bristles are clean, and the machine is off while you fit it. This is how to use a Kärcher wash brush on a K 2 to K 7 gun: lock the head, rinse grit, then brush with light pressure, and leave the WB 7 Plus lever alone while the trigger is pulled. Product ranks stay on the [Kärcher washing brush comparison](/hub/compressors/kaercher-washing-brush). Products Compared editorial team, 19 October 2026, using the WB 7 Plus manual BTA-5809567-000-01 and the amazon.co.uk review themes. We did not film a wash.
The brush only helps if it is seated, the bristles are clean, and the machine is off while you fit it.
The brush only helps if it is seated, the bristles are clean, and the machine is off while you fit it. This is how to use a Kärcher wash brush on a K 2 to K 7 gun: lock the head, rinse grit, then brush with light pressure, and leave the WB 7 Plus lever alone while the trigger is pulled. Product ranks stay on the Kärcher washing brush comparison. Products Compared editorial team, 19 October 2026, using the WB 7 Plus manual BTA-5809567-000-01 and the amazon.co.uk review themes. We did not film a wash.
Our top picks
| Badge | Product | Fitting | Functions | Weight | Note | Price | Offer |
|---|---|---|---|---|---|---|---|
| Best overall |  Kärcher Kärcher WB 60 soft brush | Union nut on the gun | Brush only | Not stated | 9.1 | about £17.94 | View offer |
| Best value |  Kärcher Kärcher OC pet wash brush | Trigger gun | Shower spray and studs | 70 g | 6.4 | about £13.49 | View offer |
| Alternative |  Kärcher Kärcher WB 7 Plus 3-in-1 | Locking ring on the gun | Foam, flat spray, soft brush | 779 g | 8.4 | about £34.99 | View offer |
On this page
Fit the head with the machine off
Switch the washer off before the bayonet moves. The WB 7 Plus manual is the sequence we can cite: unscrew the union nut, press the bayonet, turn it 90 degrees clockwise until it engages, then tighten the nut. Extension tubes are allowed. The WB 60 listing describes a union nut and does not print a different angle, so do not invent one. Seat it, then tug the head before you pull the trigger. A leak is a seating problem, not a reason to tape the joint. Do not change heads while the gun is running. The manual forbids turning the function ring with the trigger pulled.
Pre-rinse, then brush with light pressure
Loose grit in a soft bristle is what marks a surface. Knock dirt out of the head before it touches paint, glass or a shutter, and rinse the panel with the brush held off the work. The WB 7 Plus manual puts brush mode after a flat-jet pre-clean: bristles free of dirt, light force, and a pass from the bottom upward. Do not stand the brush on its bristles. The WB 60 has no tank in the Amazon bullets, so detergent goes on the surface first. One UK review of a K 5 says the machine cut out halfway through a car and needed a cool-down. Let it cool. Distance figures for paint are on the Kärcher wash brush for cars page.
The three WB 7 Plus modes
The lever gives you a flat jet, a foam jet and the soft brush, and you set it before the water is flowing. Do not turn the function ring while the gun is pulled. On a sensitive or painted surface the manual says at least 30 cm, keep the jet moving, and test a hidden spot. Kärcher’s car article prints 15 cm from paint for a flat jet. Follow the manual for the head in your hand. If the foam looks weak, tilt the foam nozzle slightly downward or refill. Brush mode is last, with light pressure. Choosing between the two heads is WB 60 vs WB 7 Plus.
When to stop
Stop if the joint leaks, if the machine cuts out, or if a jet points at skin. A high-pressure jet can break skin at about 100 psi, about 6.9 bar, which SafeContractor’s guidance treats as an injection injury and a surgical emergency. Do not point a K-series lance at a person or a dog. The pet brush is a different, low-output head and does not belong in this K-series sequence. Call a professional if the inlet has been adapted and you cannot tell whether backflow protection is still there, or if the cable or the gun is damaged. The buying guide separates the K-series bayonet from the OC 3 pet brush.
Common questions
Can I add an extension lance?
Yes, if it is a Kärcher extension the gun will accept. The WB 7 Plus manual allows extension tubes between the gun and the head. The reach problem that shows up in a WB 60 review is flex and creak at the collar over a van, not a ban on extensions. Support the head so the joint is not the thing holding your weight at arm’s length.
Which way do the bristles face when I put it down?
Up, or at least not taking the weight of the head. The manual says never stand the brush on its bristles, because dirt stays in the nylon and comes out on the next panel. After rinsing, shake the head and leave it drying bristles upward, somewhere frost-free. A head parked face-down on the drive is how grit gets into tomorrow’s wash.
Why is the foam weak?
The tank is small, and UK reviews say the foam is weaker than a separate bottle. The manual’s own remedy is to tilt the foam nozzle slightly down or to refill. A half-empty tank held upward will look feeble even when the washer is fine. If you need thick foam on a whole car, a dedicated foam lance still does that job. This head does not replace it.
Why did the pressure washer stop halfway through the car?
One UK WB 60 review says a K 5 cut out mid-car and needed a cool-down. Treat that as one report. A long brush pass can ask the pump to run continuously, and many washers stop themselves when they overheat. Release the trigger, let it cool, and do not bypass the cut-out. If it stops at once with a leak at the nut, refit the head before you blame the motor.
Can I change heads while the gun is running?
No. Switch the machine off, release the pressure, then unscrew the nut. The WB 7 Plus manual also says not to turn the function ring while the trigger is pulled. A spinning bayonet under pressure is how a head leaves the lance. The same off position applies if you are only moving from flat jet to brush.
Related pages
Sources
Public UK sources and Kärcher GB pages below. amazon.co.uk listings checked on 19 October 2026.
- Kärcher GB: WB 60 soft surface wash brush (retrieved 19 October 2026)
- Kärcher GB: WB 7 Plus (retrieved 19 October 2026)
- Kärcher GB: WB 130 rotating wash brush (retrieved 19 October 2026)
- Kärcher UK: pet wash brush (retrieved 19 October 2026)
- Kärcher GB: adapter for garden hose connection (retrieved 19 October 2026)
- legislation.gov.uk: Water Use (Temporary Bans) Order 2010 (retrieved 19 October 2026)
- SafeContractor Guidance Note 36: high-pressure water jetting (retrieved 19 October 2026)
- amazon.co.uk listings B000BFL7DS, B0BZRNJX1L, B0CT861Z5K and B01BMB3XSG (retrieved 19 October 2026)