Karcher pressure washer hunting when stopped

[B91]

My Karcher has started hunting when I release the trigger and I have to turn off its power switch until I'm ready to start again. This is the second Karcher I've had to develop exactly the same problem. It makes it pretty useless, and for this to happen to a £300 machine that has only been used a few times each year for five years is a bit disappointing.

I can't find any repairers using Google. I'm in Solihull - does anyone know of any repairers around here, or even nationally?

 

[Jackrae]

Sounds like you may have a leak somewhere as I believe it's the discharge pressure (higher when the trigger is released) that holds the motor in the OFF position.

 

[B91]

That's possible, I'll check, though I doubt there's much I can do about it. Just checked Karcher website - no service agents in the midlands at all. Not good.

 

[jj4091]

Sorry I can't tell you what the problem is but Karchers are pretty good usually, did you leave it full of water in a place it could freeze over winter? That would result in a leak.

 

[B91]

No, it's in a heated garage - I'm aware of the danger of frost damage. As I said, the previous one developed exactly the same fault after four years of occasional use. I haven't had an opportunity yet to check it for leaks but that does sound a likely cause.

I hear what you say about Karcher but the high speed nozzle wore out very quickly and the wheels have never rotated easily, so you end up dragging the beast. The detergent dispenser no longer works either. Admittedly the pump and motor are top quality - probably the only bits actually made by Karcher - but I'm not impressed by the rest of it at all. Some competition would be good.

 

[Burnerman]

If your machine is going brrrrr. brrrr brrrrr when it's not delivering water, it's a
Plastic valve head on the top of the pump that's faulty......unfortunately this does not leak to the exterior so you won't see any water on the floor.
Karcher UK are on 01295 752083 and they do supply parts, and their helpline is useful.
John

 

[B91]

Thank you John, that's exactly what it is doing. I'll give them a call in the morning.

 

[B91]

I had time today to test the machine and see what is actually happening. It is pouring water from the bottom of the housing when running and hunting on/off when not running. I rang Karcher and they referred me to a Karcher service agent 20+ miles away who want £15 to quote for repairs and warned that there is a long delay getting repairs done. Sort of confirms my feelings about Karcher pressure washers being a bit problematic, enhanced by their saying they don't sell Karcher, only Stihl!

I decided it was time for a bit of DIY and in the process managed to free the wheels, got the detergent system working again and also got the patio cleaner attachment working properly again (it just wasn't rotating at all). I wasn't too surprised to find that I couldn't do anything about the on/off hunting but at least it's usable again for a while - at least until it gives up the ghost completely.

I won't be buying another Karcher - does any one have recommendations for reasonably priced alternatives?

 

[Burnerman]

I've always liked the KEW Nilfisk machines, if I need electric but do consider a petrol one....Honda powered if possible. The difference in power is amazing.
There's a lot of Chinese machines about with aluminium pump heads and these must be avoided.
John

 

[B91]

Thank you John. I'll keep your recommendation for when I need it.

 

[DaveHerns]

I had the hunting problem on a cheapish Nilfisk/Alto machine .It's the unloader valve at fault. One rubber O ring on a nylon valve I couldn't unscrew without using heat .8 weeks and £20 for a new valve and it's as good as new

 

[B91]

Soon the Karcher K4 stopped hunting and just ran continuously with water pouring out underneath. Repair estimate £160. It has now joined a heap of similar scrap machines at Simms in Stratford upon Avon where I bought a Stihl RE129 Plus. Just no comparison. I'm finished with Karcher.

 

[simonize]

Thank you John, that's exactly what it is doing. I'll give them a call in the morning.

I have exactly the same problem 2 the same - someone else told me about the need to change a small part - how did you get on - any success?

 

[Zephyrest]

If you have hard water
I live in an area with very hard water. I just soaked the tip of the spray lance in clear colourless vinegar overnight. It no longer hunts/surges. The acid in the vinegar eats away at the limescale which is alkaline.