Sunday, 18 September 2011

KARCHER LOST PRESSURE?

Has your Karcher Pressure Washer suddenly lost pressure?
Ever wondered how pressure washers work?

My K3.80 model lost pressure recently and it gave me a chance to find out just how pressure washers DO work - (something I've always wondered about but have never really found a clear answer to on the Web).
Unfortunately though, I spent well over £140.00 on a replacement Karcher pressure Washer before I decided to take the old one apart, (prior to despatching it to the local tip), just because I couldn't stand the thought of being without a pressure washer on hand.

but........ if I'd known that I could have repaired my old Karcher for as little as £6.74, I could have saved myself a lot of money. Grrrrrr.

After removing the wheels, various hoses and the front/outer 'housing' of the pressure washer, I found the business part of the washer nestling in the back/outer housing. Quite simply, this was a motor housing with what turned out to be the 'Pressurising' bit, bolted to the end.

This is the 'Business' end - THE PUMP

Looks big doesn't it, but its suprisingly small.
The threaded Outlet for the hose to the 'lance' can be seen on the top, and the Inlet from the garden hose is on the side.
Just behind the top 'Outlet' you can see the smaller clear plastic inlet where the cleaning liquid pipe attaches to the pump housing.
The entire Pump Housing is attached to the motor/gear housing by four bolts, (you can see two of the bolt holes in this picture).

Click on the pictures to enlarge.

















And this is the underside of the Pump Housing.
You can see that there are 3 'Chambers'.
These are just like the cylinders in a car engine, and there are 3 'pistons' in the motor/gear housing, (to which this is attached), that move up and down in these cylinders.
At the top of each cylinder there are inlet and outlet valves......... again, just like a car engine.
                             
  



















And this is my rather poor attempt at a diagram to show how the Pump works -
(Click on the diagram to enlarge)

 One BIG TIP here...... if you DO decide to remove the Pump Housing from the motor/gearbox, make sure that when you undo the four bolts, (that secure the Pump Housing to the motor/gearbox), keep the entire assembly UPRIGHT because the gearbox is full of 'black' light oil which will go everywhere if you tip the gearbox over.

Now for the crunch....... WHY DID MY KARCHER LOSE PRESSURE?

There are a number of reasons why pressure washers lose their pressure, like insufficient water pressure from the garden hose, a blocked filter where the garden hose connects to the pressure washer, etc. but if you've checked all these things and the motor's racing, (not cutting out like normal) but you are still only getting a trickle of water out of the lance, then it's probably something more serious in the pump........ just like mine.

So, take a look into the cylinder chambers of my own sick pump........ (This part of the pump can be simply pulled away from the rest of the Pump Housing) 
















In the bottom two cylinders you can see the white 'heads' of the inlet valves, but in the top cylinder, the inlet valve has pretty well disintegrated.                                                  
This was interesting, because during the few weeks prior to the washer totally losing pressure, the spray lance occasionally became blocked with what looked like very tiny bits of congealed cleaning liquid/soap, but I now realise that these tiny bits of white 'soap' were, in fact, bits of the inlet valve that had broken off.

 Now let's look at the cylinder and valve assembly a bit closer;


Above - This is looking at the cylinder and valve assembly from the other side. The three Inlet valves have little red 'caps' that can be prised off to remove the valve & spring. The Outlet valves are in the middle and are held in place by the small assembly that I have pulled out and shown in the right of this picture.


 And here are 2 Inlet valves, the 'shattered' valve at the top clearly shows the damage. The second valve is intact. You can now see just how small these valves are when compared to the pound coin. They're only little bits of plastic, but they get a darned good hammering when the pump's running, so it's hardly suprising that they eventually give up the ghost.

With this shattered Inlet Valve in place, the pump was just forcing the water back into the garden hose rather than through the outlet valves to the lance. Sucking the water in and blowing it back where it came from was what it amounted to!!

Luckily, I managed to find a set of 'replacement' valves on the exceptionally good Espares website - www.espares.co.uk - listed as Karcher Pressure Washer Moulded Part Kit  all for just £6.74 incl VAT & postage !! (Aug 2011), and they arrived 2 days later, took about 5 minutes to fit, and after another 15-20 mins of re-assembling the entire pressure washer and connecting it to power and water, Bingo! a perfectly functioning Pressure Washer again.

I'm now the proud owner of TWO Karcher Pressure Washers....... but I didn't need to be.

If you start to experience occasional 'blockages', in the lance, that appear to be very small bits of white plastic, it could be an indication that pump valve problems are looming.
And if your Karcher eventually loses all pressure, but the motor is still running, (even though you've checked supply water pressure and filters), then I would suspect the cylinder valve(s).

Don't just throw the washer away - open it up and have a look - after all, what have you got to lose?

You never know, you too might be able to repair your washer for a little over £6.00.


170 comments:

  1. Thanks for sharing this, fortunately I did take my kärcher apart before buying a new one but not before reading your post, so the oil from the motor went all over my kitchen countertop. Do you happen to know what kind of oil it requires?

    The problem with my pressure washer is actually different than yours, the control head is leaking due to frost damage I suspect, which is going to cost me about 35 euro to replace. Still much better than the 104 euro that kärcher asks and certainly better than buying a new one.

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    1. it is not oil it is synthetic high temp grease using engine oil is too thin here is what you need for K1 K2 and K3 domestic KARCHER 50ml Viscous Oil Thermoplex ALN VP 2 For Domestic Machines order no. 6.964-092.0

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    2. KARCHER 50ml Viscous Oil Thermoplex ALN VP 2 For Domestic Machines order no. 6.964-092.0
      its not oil its much thicker high temp synthetic grease.

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    3. Thanks Morgan - VERY useful information

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  2. Hi Paul,
    Thanks for your comments, (and sorry about your kitchen countertop!).
    With regards to oil, you can buy "Karcher Pressure Washer Engine Oil" off the internet. It generally comes in a 1 litre bottle and costs around £25.70 (approx 31.81 euros), so it's NOT cheap.
    Annoyingly, I could never find out what grade the oil is, so rather than fork out loads of money on the real thing, I simply used a good quality engine oil, (that I had in abundance in my garage), and put about 1 litre in the housing.
    Now, that might have been a daft thing to do, but I reckoned that if it's good enough for my car engine, it's good enough for my Karcher.
    I'm not sure where you live, (talking in euros and countertops), but I'm sure you'll find plenty of local 'online' suppliers if you want to use the genuine oil. As we both agree, if you can do it yourself it's a darn sight cheaper than either having it repaired, or buying a new one!
    Good luck with the repair, (and fitting a new kitchen).
    Regards
    Smugdane

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  3. Thanks, I live in the Netherlands and I now found an online shop that sells the Kärcher branded oil, but it seems to be just regular 15w40 engine oil, nothing special really. I did some further searches and found this post by a guy in germany who ended up phoning a kärcher service center and asking what kind of oil to use, they told him that any engine oil that's not too thin would basically do, such as regular 15w40 oil. The oil is mainly there for cooling purposes he says. So I'll get some regular oil at Halfords or so.

    http://www.wer-weiss-was.de/theme131/article4039500.html

    (page is in german)

    Best,

    Paul

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  4. btw that guy also said to fill it up with oil until approximately 1 cm below the edge.

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  5. Cheers Paul - That's really interesting data that you've supplied, and I'm sure that it will help others looking for similar information.
    Perhaps my use of good quality engine oil wasn't so dumb after all. It did make 'logical' sense to me at the time. As it happens, my 1 litre of engine oil did pretty well fill the housing to within about a couple of cms of the top, (but a heck of a lot cheaper).
    Once again, thanks so much for your input.
    Mijn beste wensen overbrengen.
    Smugdane

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  6. Great article and may possibly save me a "Senior's Moment". I had a cheap washer (£34)from B&Q that lasted me 6 years before finally giving up. I bought a Karcher K3.500 as I figured at least it could be repaired if anything went wrong ( Ha HA HA). After 2 years of very occasional use it now surges when trigger is not depressed and the water is leaking out the bottom as well as the loss of pressure. AT least now you have shown at least there ways around scrapping and buying a new one, which is what all the blogs say on Karcher Forums (not surprisingly!!!) Many thanks for the info but my dog could roll over - how can a great dane type????

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  7. Hi Ticked Off - I'm glad that you found the blog of interest.
    Other than the problem outlined in my blog, I had an earlier problem that was almost identical to the one that you've outlined. On that occasion, I traced the fault to a fracture in the 'Washer Outlet Connection Cover' (go to http://www.espares.co.uk/ and search for Stock Number: ES538457 for a picture. This part is only about £3.59, and it took less than 15 minutes to replace.
    To confirm where my Karcher was leaking, I simply unscrewed the Karcher housing and removed the front panel. I then laid the machine on it's back (so that all the components stayed in place), then I re-connected the inlet hose and lance hose, plugged in and switched the unit on, and clocked where the water was leaking from. That confirmed the defective part in minutes, and a search on E-spares located a replacement part very quickly.
    Hopefully this may help, so good luck.... it's a very quick and easy repair to make if that's what it is.
    Oh yes, by the way, if your dog can only roll over then shame on you as his master. Don't under estimate the skill of the Great Dane especially when trained to type from the age of only 6 months!!!

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    1. Hi smugdane
      The saga continues. I stripped own the washer last night following your excellent sketches & photos. The little valves look OK and the pistons seam fine. Rebuilt the whole thing and tried it today - the pressure has improved but I still get the pulsing when the trigger is off??????
      I will try your trick and switch it on with body removed. Why does Karcher have so many different models??? I suspect that way each seller can quote lowest selling price for his unique model number I suspect I tried e-spares but the only parts they show for a K3.550 are a pair of gloves and a pair of wellies???? And this is supposed to be the Anniversary Model??? I wonder which models use the same parts - surely many parts are identical through the mmodel range??? WIll keep you posted and thanks for the help - couldn't find help anywhere esle and I hate to throw out a 2 year old pressure washer

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    2. Hi Smugdane
      Can you give me some advise? Stripped the casing off the Karcher to see what is leaking and found a lot of pressure coming out of this region (See Photo)

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    3. Hi - Regrettably I'm no Karcher expert, I just apply an element of blind faith, DIY and common sense when repairing things.
      If I have understood your description properly, I take it that you are getting high pressure water squirting out around the pump unit, (which is what's shown in the pictures on this blog page) and, if that is the case, then I would suspect one of the rubber seals has perished or the pump casing is split.
      It's difficult to know without seeing it first hand. If you can't see exactly where the water is coming from, I can only suggest that you remove the pump (as described above) and carefully examine the casing and each of the seal/gaskets. That may at least identify the problem.
      Sorry I can't be more helpful than that.

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  9. This comment has been removed by the author.

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  10. Where does the oil go into? I've just stripped the pump off, unfortunately the oil has leaked...

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  11. Hi Anonymous - Imagine that the machine is upside down and that you've just taken the pump unit off 'the top'. After removing the pump unit, you will be looking down into a 'chamber' and you'll see the Swash Plate (See the drawing in the blog above). The oil goes straight into that 'chamber', but make sure you put the pump unit back on and tighten the bolts BEFORE you turn the unit upright again, otherwise you'll have oil all down yer leg!!!
    Hope that helps.

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  12. Hello. Just wander if any one had a problem with karcher pulsing while trigger is pressed down (ON) and water pulses as well. I have stripped one down maybe 4 time nothing suspicious. The same type of pump as on pictures.

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  13. Hi Anonymous. I'm afraid that I'm not a Karcher expert, so I'm probably not the best placed to give advice on your 'pulsing' problem. However, the official Karcher Outlet website does give some useful advice on the most common problems, and their advice on pulsing is as follows;
    •If the machine is pulsing when on standby, is the garden hose supplying the pressure washer fully uncoiled?
    •If the machine is pulsing whilst in use, it may be that the accessory you are using has a blockage. Clear by soaking the accessory in warm soapy water and then rinsing out under the tap.
    Their website is: http://www.karcheroutlet.co.uk/Troubleshooting.asp
    There are also some other remedial suggestions on various web forums, so I think I'll have to let you try some of the suggestions already available online rather than 'act the expert'!
    It's probably something quite simple, so good luck with sorting it out at minimal cost.

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  14. My Karcher washer, is a 330M model, it is working but not in overdrive with full pressure ?. I would appreciate any help in this matter

    Regards.

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    1. Hi Anonymous - I have to level with you and say that I'm no Karcher expert or engineer, but just a simple DIY geek who likes to try and do his own repairs, so I'm not the best person to offer advice. I'm not sure if you've got the user manual for the 330M, (which has a trouble shooting section at the back), but if you haven't, this link should give you the K330M manual, which might help you: - http://www.rjbowers.com/parts_manuals/k330m_om_1994-9_1228152660.pdf
      (you might have to copy this link and paste it into Google, or whatever IE that you're using).
      If you try all the most common 'faults' listed in the Troubleshooting section and still have low pressure, then I would be suspecting that the Pump Unit has a faulty valve(s), or seal, and you can either take the unit apart and see if there's anything obviously wrong, OR you will need to take it to an authorised Karcher repairer, (which naturally is what Karcher strongly recommend).
      I'm sorry I can't be more help for your model, but good luck in getting it back to full life.

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  15. On Saturday I bought a Karcher 2200 at a garage sale for $10 CAD. The owner described that the unit would work fine for a bit then lose pressure. I knew it had to be something simple :) Thanks for the excellent info! Cheers!

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  16. Hi Anonymous - I'm really glad that you found this post useful. Good luck with the repair.

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  17. Hi, I have a K3.80MD which is leaking water from the vicinity of the detergent connection on the pump. I have not been able to remove the pump from the metal housing because the connector is in the way. I have tried to turn it so it will go through the recess on the housing but it will not move, I do not wish to break it so I have not tried too hard. Any ideas please. The machine still works well but the leak appears to affect the pressure switch.

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    1. Hi Anonymous - I'm really sorry that I can't help you on this one. I've never taken a K3.80MD apart (yet), so I'm not in any position to give any advice. The best that I can suggest is that you search for "K3.80MD" on YouTube because, in the past, I have found some really good videos that take you through exactly how to dismantle repair and re-assemble just about everything from a washing machine to a hairdryer. Hope you find some useful guidance there. Good luck.

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    2. My K3.80 had the leak and pressure switch failure so I took it to bits without the brilliant "run it with the cover off" advice. It turned out that the "O" ring on the detergent inlet was nipped in assembly or pushed out like a hernia causing significant leak and no detergent flow. To get it off (the reason for the reply), I used a gentle tugging with gently set Mole grips and pushed the plastic assembly through the formed metal plate with the other hand.

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    3. Hi Anonymous - Thanks for posting another useful tip for Karcher users.

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  18. i have same model k3.80md with same problem i managed to turn it using a pair of pliers it is only a push fit and spares are available, i need a new control head and to top up the motor oil that spilled out opps! keep it all upright!

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  19. Hi I Bunn - It's like I said in my 'One Big Tip' (in the blog above), if you unbolt the pump unit from the motor/gearbox, keep the body of the gearbox upright or you'll have dirty oil all down your trousers !!!!!

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  20. Hi smugdane It started off upright until the worlds biggest wasp decided to try and enter my ear, a small girlie moment later and the damage was done!!!

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    1. The wasp was probably only trying to help.. but Hey Ho!

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  21. Hi, I found the oil grade for my motor (k3.80md) on espares and buyspares shows castrol edge 10w60 at £44.49 and £49.99 for 1 litre. If you wanted the same castrol oil it is available online/in store from eurocarparts for £16.98 and if your quick use oilspill30 promo code for 30% off making it £11.89 a considerable saving! Well i got some and will try it soon... fingers crossed

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    1. VERY useful information - thanks.

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  22. Hi what is the underside of the Pump Housing called? where you have the 3 chambers? i have a K3.68M. somehow one of the 3 chambers has a tear in it which is leaking water.

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    1. Hi Roberto - I think you'll find that this is called the 'Cylinder Head'. If you put 'Karcher Cylinder Head' in your search engine, (Google or similar), they are available from a number of sources such as e-spares, Ransoms etc, and are in the region of £14.00. Hope this helps.

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  23. Thank you smugdane. i found what im looking for thanks to your help.

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    1. Glad to have been of assistance -

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  24. Brilliant! do you see the price of the latest ones. Mines stared to hunt when I Put a drain hose on. It hunted faster and lost pressure nearly a bin job until I found this site.

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  25. I'm glad you found this blog useful! Hope you get your washer going again for a fraction of the cost of a new one.

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  26. I have a Karcher K499 and the water is being delivered at a lower pressure which only becomes obvious when I use the T racer which causes the unit to pulse, I have stripped it down which is relatively easy and run the motor out of its casing with no obvious leaks, I did look at all the parts from the head which I stripped with nothing obvious, but only visually examined the cylinder assembly which looked ok, but i'll have another look. When I removed the 4 large bolts it exposes the engine pistons and the bearing, this only contains grease, am I to presume that the oil is in the lower cylinder, and if the little pistons in the cylinder are ok is there anything which should be obvious, all the 'o' seals are ok.Thanks

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    1. Hi Martin - I'm afraid that I'm not familiar with the K499, so I can't pass comment on your query about the "oil being in the lower chamber" and I wouldn't feel confident in giving any advice in this respect. However, when I took my own Karcher apart, the defective 'valves' were clearly evident. If close examination of the various parts of your own K499 look totally OK, and there are no evident leaks, then I personally would suspect that there may be insufficient water pressure getting to the pump. I know this might be stating the bl*****g obvious, but have you checked that the inlet filter is clear, and that there are no obstructions in the hosepipe supplying the washer? ('Pulsing' is normally associated with low incoming water pressure). If all that's OK, have you tried running the machine without the lance hose connected to the machine, (can get a bit wet!!), just to see what pressure you're getting from the washer outlet WITHOUT the lance and hose connected? I mention the latter only because you might simply have a restriction or blockage in the lance hose. Other than trying the obvious things, I'm sorry that I can't be much more help. Maybe another 'reader' has had a similar problem who could offer some advice. Anyway, good luck, and if you do find out what's wrong, please post the results, as this may also help other readers.

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  27. I cannot undo the screws on the body of my K2.385,, handle is off no problem but I cannot figure out what the other screws are... no allen key or screwdriver that I have seems to fit... is there a special tool ??

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    1. Hi Paul, I believe that they are TORX headed screws, (star shaped rather than Pozzi, Phillips or slot headed). If you haven't got a set of Torx headed screwdrivers you can often still undo them using a small slot headed screwdriver, as long as you press down hard to keep the slot head in the 'grooves'. You might risk minor damage to the screw heads, but without the right 'bits' it's probably the only way to undo them.

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    2. Many thanks... Torx heads are a new one on me.... why make
      life so complicated.... just use screws.... will try and find a torx head screw driver... thanks again

      regards

      Paul

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  28. Found I had a set of Torx screwdrivers...wish I had not... got the back off...
    undid the motor housing bit a the bottom and along with the oil... out came all
    sorts of bearing and cogs and things.... Karcher said they would repair for
    £67.00 ish .. should have listened as its now in the bin in bits.... that what you get for thinking you can repair things when you are too old to have the patience...
    anyway great blog and good advice etc... what jet spray do I get next....must be a cheapy from China I reckon...

    all the best

    Paul G

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    1. You're NEVER to old to learn new tricks Paul ! (It's just that the tricks work about as well as Tommy Cooper's did !)

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  29. Hi all
    My very little used Karcher K3.97 has started to pulse as soon as you turn it on plus the pressure output from both lances has reduced by about a third.
    I took the pump apart and although all looked ok I ordered and fitted a new cylinder head but this hasn't sorted the problem.
    I also today removed the motor from its casing but there was no signs of burning either visually or by smell.
    I have also connected the garden hose and lance whilst the casing is removed but no leaks are visible.
    I really can't afford a new pressure washer plus as I have said this one hasn't had much use probably 3 hours in the years I have owned it.
    When it pulses you can see a small valve that the detergent pick up tube is connected too move up and down.
    Any ideas would be appreciated.

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    1. Sorry to say, but this problem is not one for which I have had any experience, so I can't offer any helpful suggestions. Hopefully, other readers might come to the rescue. If you ever DO find the reason for the problem, please do post details on this blog so that others can learn from your experiences. Good luck - hope you get it fixed soon.

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    2. Will do. I have ordered a tube of silicon grease so once that arrives I will take the pump apart again and lubricate all the O rings and see if that makes a difference

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  30. Just an update, today I fitted a new upper casing of the pump which includes the detergent valve and I'm pleased to report I now have full pressure plus the pulsing of the motor has now stopped.
    I too purchased a replacement Karcher before deciding to attempt a repair so I now have two pressure washers!

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    1. Thanks for the update Paul. It's always useful to know how people, like yourself, manage to overcome these frustrating technical problems. Like myself, you now have TWO pressure washers, but at least if one stops working we both have a 'standby' whilst we try and repair the other.

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    2. i had the same problem, the part you are refering too is called the control head

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  31. Hello Smugdane. I am just about to get Torx tools to open my Karcher 411A power washer but I don't want to be like Paul Gann above and regret it if I can't put it back together again. I can't find a manual for it on-line or indoors. I am more than half way through washing my slabs and want them finished now. I shall look for Torx tools indoors but feel I need to go to B&Q for them. The motor sounds strong and has plenty of power when I put the water hose through it without the power spray. But little power coming through the power spray. I shall let you know how I get on.

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    1. Hi Jane, I wish you success with your repair. If you have a mobile phone, or other camera handy, I always think it a good idea to take regular 'shots' as you dismantle the washer, and be methodical as to where you place the various screws and bolts once you remove them. This way, you should be able to re-assemble again without too much worry. One word of advice, (that I mentioned in my blog above), DO keep the pump housing 'upright' when you remove the pump from the main motor body, because it is full of thin oil which will go everywhere if you're not careful. Thanks for your post and good luck...

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    2. Hi again Jane - Just as an update, the 'E-Spares' website have User Manuals available for download, including one for the K411A, and there are also good 'exploded view' diagrams available on Karcher's web site. Hope that helps?

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  32. Hi , I have a karcher k3.99 . The motor sounds ok but there is no water coming out at all. (a bare trickle ). How do i get at the filter or where is it ?
    Thanks

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  33. Hi anonymous - If you go to the following web site; http://www.ransomspares.co.uk/parts/brands/karcher/pressure-washer-spares/k3.99m%20eur%20(1.423-230.0)/
    there's an 'exploded' view of the K3.99, and this will point you in the right direction as to where the water filter is located.
    Have you checked the water flow without having the high pressure hose and lance connected to the main body? It's just that if there is plenty of pressure at this point, its more likely that the lance is blocked. If there's no pressure at THAT point, then it could be the water filter, insufficient water pressure from your garden hose connection, or one or more broken valves in the pressure housing. Good luck.

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    1. Hi! I have a k3.500 and the motor now continues to run after the trigger has been released and there is a serious drop in pressure and an increase in leaking water. I thanked the heavens when I came across your article and proceeded to strip it down; only to find that I hadnt got the strength to undo the pump case retaining bolts. I have since put some penetrating oil on them in the hope that they may loosen but any tips would be welcome

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    2. Hi Tony B -
      As I've mentioned to previous reader's enquiries, I'm not a Karcher engineer, (or any other kind of engineer for that matter), but simply someone who likes to know how things work by taking them apart!
      Anyway, that said, I can't offer any 'tips' about undoing the pump case bolts other than trying some penetrating oil like you're already doing, so I hope that works...... a hammer sometimes also has the desired results (only joking!).
      If you manage to identify the problem, please DO re-post on this blog and let readers know how you get on. - Good luck.

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    3. Thanks Smugdane. I managed to borrow a large Alan key that fitted the bolts and by using a metal tube as an extention, managed to exert enough pressure to remove them. So the pump has been stripped down. However I could not find any obvious faults so have ordered a new valve set and a new cylinder head unit. The photo of your cylinder head unit, differed from mine and I had no caps on the valves to lever off. (If you get my guist). Anyway I only hope that this solves my prob and will let you know later. Total cost so far £29.

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    4. Thanks for the update Tony - I really hope that you will solve your problem with the new parts. Let's face it, even £29 is a darned bit cheaper than a new washer!!

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    5. Hi smugdane. Final roundup!! Put all together again. Managed to get a little more power but there is still a big leak coming from under the capacitor housing and I am unable to fathom out how to get at it. It all looks like its held together by plastic clips and looks very fragile. Anyway, Ive managed to get the terrace finished and that was my main aim. Thanks again for your counsel Tony

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  34. Hi smugdane - I have a k2.56 which out of the blue has given up.. I have a trickle of water coming through and the motor is going round fine.
    I have followed countless youtube videos and read many blogs which have resulted in me finding the problem way down in the gear box.

    There are two round gears which rotate around a central gear, these have shattered and need replacing. I have cleaned every last spec of metal shard from within the housing. This leaves me with one problem... Where to buy the replacement gears from???!!!! Any ideas? As I cannot find any and even looking for a part number throws a blank...

    You can help and you know who to call.... A team needed!!

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    1. Hi Anonymous, I'm not familiar with gears deep down in the bowels of the motor, but it sounds like a new or refurb motor to me!
      I seriously think that the only way of getting your hands on these two gear wheels is to contact Karcher Service direct. I really don't think you'll find spares of this kind other than through Karcher, but hats off to you for stripping the machine down and giving a DIY repair a shot.
      If you have any joy, please do re-post and let our readers know how you get on.

      Delete
  35. Hi smugdane, Great article which has been very helpful to me in understanding the workings of the pressure washer. Like you, I bought a new Karcher washer when my K3.99M became faulty, because time was of the essence. I am now trying to fix the faults.
    Briefly, I lent the machine out; when it came back it leaked like a running tap as soon as the water was turned on. The inlet elbow looked like it had burst (literally like an eruption) on the point of the elbow.
    I replaced the elbow but then the machine leaked from the cylinder head. I found one of the three grooved rubber rings was split; I replaced all three. The machine then appeared to work ok but seemed down on pressure. Although the valves etc had looked alright, I surmised that maybe the valve springs were weak, so I replaced the complete cylinder head. The only difference this made was that when I turned on the power the motor ran continuously, whereas before it (correctly) only ran when the trigger was operated.
    I have tried the old lance and gun fitted to my new machine and they are ok. I did notice a few weeks ago that there was a kink in the high pressure hose; I straighten it and now cannot find it, so I was wondering whether there might be an obstruction in the hose. The new machine has a different connector. Having said that, I tried running the faulty machine with the outlet hose disconnected: water came out but at what seemed to me to be less than the mains water stream. I would appreciate any advice you can offer. Thanks.

    ReplyDelete
    Replies
    1. Hi colbee - Wow - seems like you've really been hands on to try and repair your K3.99M washer! Not sure that I can be of any real help but, for what it's worth, these are my thoughts, (and they're ONLY thoughts).
      Based upon what you have described, there could be two problems;
      1. There could be insufficient water pressure getting into the washer via your house hose supply. If your house hose supply is OK, it might be worth checking the inlet filter on the washer to make sure that there's no debris restricting the water pressure entering the washer. If it were my machine, I'd firstly do what you've already done, namely connect the house hose to the machine, and with the pressure hose and lance left off, see what pressure of water comes out of the washer. Then I'd VERY BRIEFLY switch the machine on and see if there is any improvement to the water flow. If the outflow of water isn't great, then there is most likely some blockage and/or restriction of the water from the point of mains water entry, through to the pressure hose connector outlet, so start checking filters etc.
      2. Secondly, you say that the motor runs continuously WITHOUT pressing the trigger on the lance. This sounds like it could be a faulty pressure switch!
      If you visit the following web site, (you might have to copy and paste this link into your web browser) http://www.ransomspares.co.uk/parts/brands/karcher/pressure-washer-spares/k3.99m%20eur%20(1.423-230.0)/
      there are some good 'exploded' views which are very helpful for the K3.99M.
      I don't know how much you've spent so far, but obviously there comes a point when it's not cost effective to KEEP buying spare parts to try and get an older machine to work again, but many of the parts are quite reasonably priced and available, so it's probably worth going that extra mile now that you've done so much work! (In any case, it's always good to have a spare washer, and the sense of achievement, when you do get it working again, is well worth it).
      Good luck, and please do re-post to this blog if you manage to resolve the issues.

      Delete
  36. Hi there, first off let me also add my appreciation that you've firstly taken the time to write this up and then to follow up the questions openly and honestly thereafter! Its great to see and well done! :)

    Like yourself I have a K3.80 which sprung a leak and also like yourself I'm in the same frame of mind as you! I'm no Karcher pressure washer engineer but nuts are nuts, bolts are bolts and springs, valves and O rings are... well, you get my drift! If its broken then whats to lose?! (Apart from some oil!)

    Background info - washing my car one day the pressure washer lost pressure and the motor was constantly running... When I looked closer I noticed the stream of water running from the plastic casing. Stripping the plastics off and running it showed water running out of the area around the washing fluid inlet but it was also running from the other side which I initially thought was where the leak was. The final fix is yet to be achieved but below is what I have done so far!

    I started by finding an exploded view of the 'gubbins' of the pressure washer on ransom spares.co.uk and I strongly recommend everyone does this to locate all moving parts and O rings before taking it apart. If its a leak somewhere then garden hose pressure should be enough to locate it but you may have to orientate the pressure washer (with plastics off) the right way to see where the water is actually coming from as opposed to where its running from... I'm speaking from experience here as I thought after my first strip down and rebuild to check that it was indeed coming from the triangular rubber seal that sits between the piston non return valves housing and inlet/outlet halves, I must have nipped the triangular seal so yeah it was then leaking from there and removal of it showed a split seal! Spare form seal ( Ransom Part number RS512894) ordered via Ransom (£1.95 for seal and £1.95 for postage) and fitted yesterday but the leak remained!! Obviously I had fixed my damage but the original damaged seal remained! Duuuuh

    I thought the silver metal cover (shown in your photo above) wouldn't come off when first stripping it down as it seemed 'at one' with the plastic but after some focused prizing with a small flat blade screwdriver today the metal bottom came off along with the white plastic washer fluid inlet. This inlet is a pushfit piece, held in by another rubber o ring and it is this O ring that has a characteristic degradation split in it (shown as part of the assembly named 'front housing modular compact' (item 3) on Ransoms website). I can't seem to order the O ring separate from the assy so I'm going to have a poke around at work and see if, by chance, there's something the same size before hunting around on the net any further.

    Apart from spilling some oil and causing some damage by nipping that triangular seal, its been a lot of fun seeing how this works and I'm certain this leak can be fixed. There aren't that many seals that can split and to be honest, if you're paying the same price for postage as you are for a seal then you might want to consider buying all the main seals in one go.

    Power to the DIY people!

    ReplyDelete
    Replies
    1. Hi Glen, and thanks for posting such a comprehensive and positive description concerning repairs to your own Karcher.
      I fully agree with you that it IS quite good fun taking items apart and finding out how things work and, as you rightly say, what have you got to lose! Power to the DIY people indeed.
      Thanks again for your support.

      Delete
  37. Hi All,

    I have a K2.59M pressure washers that no longer has pressure, even though the motor spins fine!

    So I decided to strip the unit only to find that it is not the usual culprits? To cut a long story short, behind the swash plate and bearings there are what appear to be 2 white nylon planetary gears, which in my unit have disintegrated into small bits. Try as I may i cannot get these as spare parts not even from Karcher UK? Which is ridiculous as this would seam to be a part that would fail (being made of nylon/plastic!) so far i VERY unimpressed with Karcher as it would seem that I need to replace the whole thing just because of 2 plastic gears!

    Definitely will NOT be buying another one of a there units as I'm sure all there motors would have the same basic design and this looks like a weak point in that design!

    Grumpy old b*stard

    ReplyDelete
    Replies
    1. Hi Anonymous - Sorry to hear that you can't get the spares... that's a real bu**er. I've just had a look on a website called Ransom Spares - (this is the link) -http://www.ransomspares.co.uk/diagram/karcher/pressure-washer-spares/493238/k2.59%20m%20epc%20eu%20(1.672-400.0)/
      and I can see the two cogs that you refer to. MAYBE it's worth giving Ransom Spares a call?? They do say on their site that if the part you want isn't listed to give them a ring. Other than that it looks like a new washer..... b*stard!

      Delete
  38. K4.99 failed spectactularly yesterday. Lost all pressure at the rotor head and looked round to see water and foam (from cleaning agent in use) pouring out through the front of the machine. Motor/pump was still running and the flow stopped when power was disconnected and restarted when power was re-applied.
    Thanks to here, opened up (8 torx screws) and crack found in the plastic outlet elbow.
    Quick, cheap repair when compared to cost of replacement pressure washer.
    Very likely weakened by frost damage. Water can pool at this point.
    In future, it will be stored indoors over winter

    ReplyDelete
    Replies
    1. Nice one Mark - Glad you found my blog helpful. The very same thing happened to one of my own Karchers about 4 years ago, and it was such a quick and cheap fix.

      Delete
  39. Hi, smugdane...
    I have problem with my karcher 3.16

    My karcher wont suct water supplay from water bucket anymore..
    Only working when pressurized water supplied in suction..

    I was 4 times disassembly the pump, filter, piston, seal, and no broken sign..

    Is the karcher spec only using pressurized water supplay or no?

    ReplyDelete
    Replies
    1. Hi wwn - I'm no expert on Karcher pressure washers, but as far as I'm aware, kits for feeding from water butts etc. are suitable for use on any K3 or K7 series washers, so your machine should be OK for that purpose.
      As your washer works fine when using the mains water as a supply, it sounds to me like the hose you use from the bucket is blocked or kinked! Have you checked that your water bucket hose is absolutely clear and free flowing?

      Delete
  40. Water hose was very clean and free from any dirt (1/4inch flex, transparent hose).
    Is the seal for piston available or sold separately from the pump assembly?
    I feel the pressure little bit degradation from new until now..

    ReplyDelete
    Replies
    1. Unfortunately I don't know if the piston seal is sold separately, so I suggest you go to http://www.ransomspares.co.uk/ and look at the 'exploded' diagrams on their site to see if you can find what you're looking for. Ransom Spares seem to have LOADS of spares for Karcher pressure washers. If you can't see what you're looking for, then it might be worth giving Ransom Spares a ring! - Good luck.

      Delete
  41. Im from indonesia, i think very pricey to buy from UK including shipment..
    I will Use this karcher until the end of service.. and will consider to buy small one like k2.14


    Thanks very much smugdane..
    Nice posting and helpfull blog...

    ReplyDelete
    Replies
    1. Hi wwn - I didn't realise that you were from Indonesia so I can quite understand what you're saying about the cost of buying spares from the UK, particularly once shipping is added. I'm sorry that I haven't really been a lot of help to you, but thank you for your kind comments.

      Delete
  42. Just want to say thanks for your article. Gave me the confidence to repair my own K3.65 Jubilee for the cost of a £9 capacitor, rather than paying for someone else to repair it or throwing it out! You are right, once you get the covers off, they are not that complex. The only complex thing about them is the plethora of model numbers - Karcher seems to have different models for each retailer! Thanks.

    ReplyDelete
    Replies
    1. Thanks Anonymous and I'm so glad you managed to repair your Karcher rather than just dump it. I do agree with your comments about the model numbers - They confuse the hell out of me as well!!

      Delete
    2. Hi If anyones interested, i just replaced the swash / thrust bearing on my K5.80 with a SKF 51108 and it works perfect now. Filled chamber with auto transmission fluid as thats all i had around. Has worked fine for a few hours since. BTW bearing is £2.50 on ebay!

      Delete
    3. Hi Anonymous, and thanks for providing a very useful tip for the readers.... nice job!

      Delete
  43. Great article and well explained man!

    ReplyDelete
  44. Thank you Victor - it's always nice to get positive feedback.

    ReplyDelete
  45. Thank you so much for this, it's given me the confidence to try repairing my own pressureless jetwash. I've given myself something to do for the weekend.

    ReplyDelete
  46. Nice one Keith - Just remember to be 'logical' as you dismantle the washer.
    If you don't manage to effect a repair you've lost nothing...... If you DO manage to repair the washer you will probably done it for minimal cost and you will feel a great sense of accomplishment!!
    Good luck.... give it a go.

    ReplyDelete
  47. Reading your blog ref Karcher pressure washer, very interesting and informative. I have a karcher K2.395 which is just under two years old and been used half a dozen times. It too has suddenly lost pressure and there are no apparent leaks. Luckily I read about keeping the pump upright before taking it apart and spilling the oil. Having done so, I found the oil to be a dirty grey silvery colour indicating it had been contaminated with water. I have since ordered 3 new oil seals for the Pistons and am waiting for delivery. Needless to say, if this doesn't solve the problem I will have to scrap the machine but will never buy another Karcher again!

    ReplyDelete
  48. Hi Neil - Glad you found the blog informative - When I stripped down my own Karcher, the oil was also a rather thin dirty grey/silvery colour, but it didn't show any signs of water contamination, so maybe this is the colour that the oil goes, and it might not be that there's a problem there? Fingers crossed, replacing the piston seals might just solve the problem...... there's nothing like the buzz when you put it all back together and it ACTUALLY WORKS! - Good luck.

    ReplyDelete
  49. i have a Karcher 4.600 and the wheels just will not turn. I have had one new set from Karcher as they split, but they still won't turn. the dealer i have spoken to says they can't do anything, they have had then before with this problem, it is just how they are because they are plastic. Has anyone else had this problem please? also the ball bearing in the turbo lance sticks most of the time and just will not wokr.

    ReplyDelete
  50. I wish I'd read these postings first. That way I might not have oil from the gearbox all over my worktop.

    I have since found sites saying the oil is '10W-30 non detergent' but nowhere can I find out how much oil to put in. Is it meant to be full to the brim, half full etc? Any advice would be much appreciated.

    Btw:

    1. What a great set of postings by Smug Dane.

    2. Karcher won't put the parts diagrams online. But the diagrams are available at a US site: http://www.pressureparts.com/treeview.aspx. complete with part numbers. Be careful as the parts numbers are for US models (with 110V electrics) but it at least gives you the name of the part and show how they fit together

    ReplyDelete
    Replies
    1. Hi Anonymous - Thanks for your very useful and kind comments. For what it's worth, you can also find Parts Diagrams for British Karcher models at Ransomspares.co.uk.
      I have never found any guidance as to exactly how much oil to put in the gearbox but, based on how much came out, I filled the gearbox to about half full and my machine is still going strong after 3 1/2 years, so I don't think this was too far out!

      Delete
  51. Hello everyone my karcher pressure washer has just stopped working for me after 5 mins of washing the car and it won't switch on now. Any tips would be great its on 18 months old thanks kay

    ReplyDelete
  52. Hi Kay - Not exactly an easy one to resolve without seeing the machine. I guess you've tried the most obvious 1st step and checked the wiring and fuse in the mains plug? If that's OK it could well be an electrical problem in the Karcher itself, such as a bad electrical connection, defunked switch, etc. Sorry I can't be more specific.... may need to go to the Karcher hospital!!

    ReplyDelete
  53. Great stuff, wonder if you can help. I have a basic K2 which has developed an internal leak. My problem is pretty basic - how to get the covers off. So far as i can see there are only 3 torx headed screws holding the thing together. One at the top in the fixed handle section and the other two on the sides on holding the electical cable inlet are and the other forming the 'holster' for the handset. I've removed all three but the 'shell' remains as tight as an immature oyster. I cannot see any other recessed screws etc. and insertion of a flat bald screwdiver in the seam does not help.
    Fact I don't see too well these days probably does not help, but I don't think I've missed anything ?
    Perhaps this model is not meant to be taken apart ?

    Any ideas much apprecaited

    ReplyDelete
  54. Hi Ray, I would suggest that you enter "Karcher K2 exploded view" in Google, then select the 'Images'. I'm sure that there will be a picture there that will indicate where all the securing screws are located. Hope this might help...... it's answered a few questions for me in the past!!! - Good luck

    ReplyDelete
    Replies
    1. This may help in finding the screws. There should be 6 in total.
      http://siteassets.ransomspares.co.uk/ModelDiagrams/734-820/tqfzqknb635689230114018961.jpg

      Delete
  55. Thanks very much for going to the trouble - you have sent a much better print than i have managed to get before. The only screw head I can find is the one marked 10 on the diagram. Unfortunately i don't see things too well these days, but as soon as some unsuspecting visitor with better sight appears I will prevail on them to have a proper look.
    Appreciate your assistance.

    ReplyDelete
  56. Hi,
    thanks for your excellent blog. My k399 started spraying water from inside the machine so as you suggested I took the cover off and tested. This showed that the elbow piece on the output side had a split along the seam. I ordered a new one so that looks good (in no small part due to you) HOWEVER I noticed that with water supply on but the motor off there is a steady stream of water coming out of the output (lance not fitted) and I am worried I also have a valve failure. From your drawing it seems likely that water will flow like this because the inlet valves only close when pump applies pressure and I think this is also true for outlet valves. Did you experience the same thing on your tests?
    Regards
    Les Folkes

    ReplyDelete
  57. Hi Anonymous - Pleased you found the blog useful - There's nothing to worry about... water WILL still come out of the outlet, even without power connected. If you attach the lance to the outlet and connect your water supply, (but with NO power switched on), pulling the trigger on the lance will result it a stream of water from the lance - no problem, the motor only puts the water under high pressure. When I use my Karcher, I set it all up, but before turning the power on, I operate the lance to let the water flow and clear without any airlocks (which will make the water sputter). once I get a regular stream of water I then start using the Karcher under power. At the end of use, I turn the switch off and operate the lance to let the residual water pressure out. Personally, I do these two things to try and put less strain on the machine, that's all. I hope that fitting the elbow will solve your problem - Good luck

    ReplyDelete
  58. Hi I hv a karcher k3 65 jubilee which had a leak on cylinder head which i replaced now i cannot get the machine to switch on hv i assembled wrongly

    ReplyDelete
  59. Hi anonymous - As mentioned in my previous replies, I'm not a Karcher expert, just someone who enjoys 'getting things working again'.. however, I can't think that simply changing the cylinder head would have any effect on whether the machine switches on or not, so I very much doubt that you've "assembled it wrongly". I take it you've checked the fuse in your plug and that any other electrical connections within the machine are properly connected and secure? It's sometime very easy to 'tug' a cable/connection when taking machines apart so worth re-checking all internal connections (with the machine unplugged from the mains supply... of course!)
    Sorry I can't be more helpful. Maybe other contributors can help? Likewise, if you find the problem, please re-post here as a help to others who might suffer a similar problem at some time.

    ReplyDelete
  60. Hi all - found this blog whilst attempting to repair my Kingcraft pressure washer, which is made by Karcher. Biggest problem was I cannot find any model numbers on it, and nothing to cross-reference it with an equivalent Karcher model. I found a PDF of the manual for it here. http://www.karcheroutlet.co.uk/Manuals/Pressure%20Washers/kingcraft-uk.pdf Last time I tried to use it, it worked for a few minutes, then started buzzing with the motor not running, whether the trigger was pulled or not. Giving it a kick got it going again once, but it refused to respond to that cure a second time! Research said that the motor start capacitor was faulty so I started a search for a replacement. The capacitor sits in a moulded tube (part of the switch assembly) and so had to be of the correct diameter & length. I looked everywhere for one to fit the bill, but all of the ones I found had a fixing bolt in the bottom. Eventually, I thought I had found one on Amazon - the image looked correct, but when it arrived today, you got it - it had a bolt on the bottom. So it is out with the hacksaw when I next get 5mins, and hopefully the new capacitor will solve the problem. If anyone can come up with a cross-reference to Karcher for this model, it would be helpful if I have to obtain parts in the future. Thanks!

    ReplyDelete
    Replies
    1. Hi Anonymous - Have you tried this site -
      http://www.ultimatewasher.com/karcher/diagrams/5970-0170.pdf
      ... or have you tried contacting Karcher themselves to try and purchase a starter capacitor directly from them??
      Good luck.

      Delete
  61. well I have just read all the problems can any one help with mine. I have a k2 karcher that lost pressure today and I notice there is oil coming out with the water when I pull the trigger. Karcher tell me I shouldn't have used it for patio cleaning and chuck it and buy another. No chance I have hardly used it in the 2-3yrs of buying.

    ReplyDelete
    Replies
    1. Hi Anonymous - the only place that there's oil in the Karcher, is in the gearbox/swashplate area, so it must be this oil mixing with the water, so I would assume that the oil seals around the 'pistons' have broken down, (see drawing above - pistons coloured orange). I'm NO Karcher engineer, but I'd bet this is your problem!!

      Delete
  62. This comment has been removed by a blog administrator.

    ReplyDelete
  63. Hi, re the oil used, i have just repaired a swash pump from a petrol washer, i phoned the agents for this machine to find out the grade of oil and was surprised to hear, i quote, use SAE30, but any motor oil will do the job, hope this helps someone, Phil

    ReplyDelete
    Replies
    1. Hi Phil - Thanks VERY much for this bit of advice, which I'm sure some readers of this blog will find extremely helpful.

      Delete
  64. Malcolm
    After 2 years using a K4 I was unable to start it, I tried many times. Bought a new K4 which started only after several attempts!! Today both new and old K4s started after several attempts. Could it be due to low water pressure?
    Using a normal house is not a very powerful spray??

    ReplyDelete
    Replies
    1. Bit weird if it's doing the same thing on TWO machines.... Don't have a clue as to why, but suspect either low water pressure or dodgy electrical socket/extension lead... Have you tried using one or both machines at a friends house, just to see if they work OK there? Maybe other readers may have a suggestion?

      Delete
  65. Thanks, Paul.
    Same problem for me on 3.65 Jubilee.
    One of my inlet valves had completely disappeared so I guess it had completely disintegrated.
    Spares on order from Kärcher direct as the parts in the link were (according to espares) not compatible for my model, dexpite lokking similar.

    ReplyDelete
  66. Hi, can anyone help me? I have taken apart my K3.550 and found that the gearbox oil must have mixed with water, it has become more of w grease. Much like the gunk found in a car with a dodgey head gasket.

    I took it apart as the problem was that pressure would drop after about 5 seconds. Is this a new cylinder head required?

    Thanks,

    Adam

    ReplyDelete
  67. Hi Adam - It's a bit difficult to assess without seeing your machine, but it does rather sound like a new cylinder head. Before spending out though, it's probably worth contacting Karcher and seeing what they might think it is? Sorry can't be more help, but maybe there are other readers who can help!

    ReplyDelete
  68. Hi Smugdane,

    Thanks for your reply.

    I managed to take a few photos, not sure if they will help? But will try contacting Karcher.

    Is there a way of posting photos here?

    Adam

    ReplyDelete
    Replies
    1. Hi Adam - To be honest I'm not sure about posting photos in the'Comments' section of the blog. You could try opening one of your photos, then clicking 'copy' and then 'pasting' into your reply. Not guaranteed, but worth a try.
      Cheers

      Delete
  69. That didn't work... But how about this?....

    https://www.dropbox.com/s/xw7eolg6hcgea75/Photo%2021-02-2016%2C%2012%2014%2014.jpg?dl=0

    https://www.dropbox.com/s/m2y6yab29xh3h75/Photo%2021-02-2016%2C%2012%2014%2020.jpg?dl=0

    https://www.dropbox.com/s/m49sj301ha1vazh/Photo%2021-02-2016%2C%2012%2014%2031.jpg?dl=0

    https://www.dropbox.com/s/e9xrge64jy59une/Photo%2021-02-2016%2C%2012%2014%2050.jpg?dl=0

    https://www.dropbox.com/s/7aicmr51bpxopr2/Photo%2021-02-2016%2C%2012%2015%2019.jpg?dl=0

    ReplyDelete
    Replies
    1. Hi Adam - That works by copying the link and pasting into the browser. Good, clear photos.
      Unfortunately, I'm none the wiser so this really is one for Karcher unless any reader has an immediate suggestion.
      If you do get to the bottom of the problem, please do re-post details back here.... it might just help others with similar problems. - Good luck.

      Delete
  70. Hi Guys
    I have a K3-350
    It will give HIGH presure ok but once I release the LANCE.
    It will not produce HIGH pressure until I go to LOW then wind
    the lance to HIGH again.
    Its ok on HIGH until I release it. Then back to LOW ok again turn to HIGH and it will continue HIGH again

    Any thoughts on this one

    Johnny Melvin

    ReplyDelete
    Replies
    1. Hi Johnny - Weird or what? Stumped me!! Maybe some other bloggers might have some ideas? If you get to the bottom of this, please DO post your conclusions on this Blog so that it might help any others suffering the same problem. Cheers.

      Delete
    2. The exact same problem but on a different model (k2.900m) and as you say the pressure is fine until I release the trigger then when I restart it is just a dribble until I turn the variable lance to low, then it blasts into full power. I did see a youtube video where they had the same fault but on a petrol washer, they said it was a Stuck bypass valve? Do smaller electric washers even have a bypass valve ? wish I knew as I can't find any mention in parts lists.

      Delete
  71. Hi all. Some great reads in here. My friends K2.56 packed in last week so I said I'd take a look at it for him.When it is turned on the motor starts up but doesn't stop. I sussed that it would be a connection problem between the motor and the pump. I stripped the washer down and unbolTed the motor section from the pump. Surprisingly there was no oil in the motor. New seals required there then. But once I looked inside the motor behind the plate I saw the 2 white plastic cogs in pieces inside. I have removed them and found that it is or should be 1 part. A plastic ring with the 2 cogs fixed to it.
    I have searched all day for this spare part. It is shown in the diagrams but not listed as a spare part.
    Probably a design feature to sell more washers by karcher. I have always found , not just in pressure washers but in other mechanical gear products that when plastic and metal meet, there is only 1 winner.
    If anyone dies know where I could obtain said part I would be most grateful.

    ReplyDelete
    Replies
    1. Hi Kevin - Many thanks for posting your comments, and a very interesting account of another fault that could occur on a Karcher washer. Thanks also for the photos. Your Dropbox link to the photos is published below. With regards spares, have you tried E-Spares? On their site they have some excellent 'exploded' views of loads of different Karcher models, with all parts numbered. I expect you've already done this but, if not, it's certainly worth a try. Good luck.

      Delete
    2. Hi again Kevin - I have just found an 'exploded' view of the K2.56 on the following link http://www.ransomspares.co.uk/diagram/karcher/pressure-washer-spares/492356/k2.56%20deluxe%20gb%20(1.672-471.0)/
      (copy and paste link into your browser).
      The gears are visible, but don't seem to have a part no. Might be a good idea to phone Ransom Spares,or even Karcher UK themselves. There MUST be spare gears knocking about somewhere!!

      Delete
    3. Hi again well done for sharing knowledge to help others. I too am trying to fix a K2.56 for a friend and have found the 2 white cogs shredded, at present unable to find replacement, just wondering if anyone has had any luck.

      Delete
    4. Hi Shane - I get the feeling that you'll only get these cogs from Karcher themselves, or you'll have to buy a complete new motor assembly. I really think that your best bet will be a call to Karcher UK. Good luck.

      Delete
  72. https://www.dropbox.com/sh/tecxvryt3umngb8/AADg7nrnJk_BJkSKJAKcS82Za?dl=0
    Here are the photos of the stripped gears.

    ReplyDelete
  73. Hi, Having read the previous comments with great interest I wonder if anyone can help me out. I have a Karcher K3.99M pressure washer which totally lost output pressure. I have followed the tips above and replaced the cylinder head and inlet/outlet manifold and also re-assembled a dodgy on/off switch. The machine now turns on and off and operated the motor only when the trigger if pressed....but still no pressure...help!
    The only thing that has me puzzled from the blog site is that members have stated in several areas that the motor unit contains oil and caution should be used not to spill it when taking the pump apart. I have tried inverting the motor when it is stripped down to the rotary cam and not a drop of oil is evident! Does this mean mine has run dry or that this model does not have oil in it? If it is supposed to contain oil where do I pour it in...in the top of the unit through the rotary cam? I have downloaded the user manual and this states that this unit is "..maintenance free..", whereas some of your contributors have stated that the instructions say the oil should be changed regularly. I am tempted just to chuck some in there and see if it changes anything....next step is the skip I think. (anybody interested in an unused cylinder head and manifold assembly that could be going really cheaply very soon?)

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  74. This blog is very helpful Paul - thanks. Off to buy TORX set to open up my non working K2 and investigate loss of pressure Michael

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  75. Hi, I have followed your advice on changing the little valves no problem and no oil leakage thank you the only problem i have now after putting it all back together i have no power any advise please.

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  76. Hi Sue, sounds like an electrical connection has come loose somewhere, either during dismantling or re-assembly, (or fuse has blown in the plug). Suggest check/replace fuse in the plug first. If that doesn't work, DISCONNECT the unit from the mains power supply, then you'll have to dismantle the casing and carefully check that all electrical wires are firmly in place/connected.
    If you're not competent with electrics, DON'T TAKE RISKS - get an electrician to do this for you as he can use a meter to check power continuity. Hope you resolve it easily.

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    1. Many Thanks I will take it apart again and see if it still doesn't work i will certainly get an electrician to have a look thanks for your advise this blog is fantastic :)

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    2. Thanks for your kind comments Sue - Fingers crossed that you resolve your problem.

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  77. Thanks very much for both your explanation and hosting what has become a forum for disappointed Karcher owners! You gave me the confidence to strip down my K3 but the heat and smell from the motor casing has made me conclude that it has died, and although I suppose I could try to replace it, I noticed that the adjacent alloy casing must have been cracked badly when the thing was originally put together and so I have lost all confidence in this washer. Goodness knows how QC missed it. Oh well, off to break open the piggy bank...

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    1. Thanks for your input MartynW - Sorry to hear that the health of your particular machine is now 'terminal'- At least you tried.

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  78. Hi
    I have a Karcher 411A. I have connected the hose and water comes out without the pressure hose connected. When I connect the pressure hose no water comes out neither with the machine plugged in or not

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  79. Hi Anonymous - When you say that "no water comes out" once you've connected the pressure hose, do you mean that no water comes out even when you press the trigger? (whether the machine is switched on OR off)? If that IS the case, then it sounds like a blockage in the pressure hose. Might be worth undoing the nozzle and just checking that there's nothing solid stuck in it. You could even see if you can 'blow' through the pressure hose when you press the trigger... (with the pressure hose disconnected of course!!) Good luck !

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    1. Hi Smugdane

      While waiting for a reply I dismantled the middle part of the wand thinking the same that there probably is a blockage. It came apart easily and now I cant get it back together. The position of the large spring is the problem and is obstructing the casing from closing. I know it sounds ridiculous but I just cant get it positioned correctly. I dont know if you have any tips. I will try to dismantle the spray end but although it turns in two positions it doesnt look like it comes apart. Im sure you are right about an obstruction as I have just tried the machine without plugging in and water comes out of the gun. You are very helpful. I have spent a lot of time today trying to find a diagram on line for the mid section assembly but cant find anything. Hope you can help. Seems a shame to ditch the machine.

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    2. Hi again - Not sure I can give you any useful 'tips' about re-assembly, other than you will REALLY need to push the parts together in order to compress the spring before twisting into position. As far as diagrams are concerned, you could try the following link: http://www.karchercenteraquaspray.co.uk/downloadable/download/sample/sample_id/15/ (you will probably have to copy this link and paste it into your google, or other, search bar - when the pdf opens, scroll down and see page 17!). Karcher are also pretty good at giving technical advice if you phone them. It might also be worth checking YouTube as there are sometimes some good posts showing exactly how to dismantle and re-assemble things. Hope you manage to resolve this.

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    3. Hi again and thanks. I have now managed to put the spring back and hope it is in the right position. I cant see what purpose the spring has so it made it harder to see where it should go. Do you know if there are any mechanical parts to the wand which could fail and cause a problem. It looks just like a thin pipe to me and cant see why it shouldnt work. Thanks for your help.

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    4. Hi there - Regrettably, I don't think that I can help much more as I'm only a DIY'er rather than a Karcher expert. Just as a matter if interest, have you tried blowing through the wand, just to see if it IS that bit that's blocked?
      If it is, there's probably 2 options: a- Phone Karcher for advice, and/or b- buy a new wand.
      It's so difficult trying to help from 'a distance'.
      Just a few last thoughts.... if it were me I'd connect the machine to your hose supply and power supply, then, with the pressure hose and wand NOT fitted, turn on the water supply and turn on the washer, (stand well clear!!) - if the water comes out of the machine at pressure, (where the hose normally fits), then it's not the machine at fault - turn the machine off and also the water supply. Now fit the high pressure hose (but NOT the wand as well). Turn on the water supply and switch on the machine - If water comes out of the pressure hose at high pressure, then everything is clear up to there!! If this is the case it HAS to be a blockage in the wand.
      It doesn't sound as though this will help but probably worth a try. I really DO hope that you get it working again

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  80. Thanks for your useful posts. My issue is: Inlet water pressure: Apparently good (Good flow when disconnected). filter: clean. Unit appears to be running normally but the outlet water pressure is only a little higher than when it is switched to off and definitely lower than it has been in the past.

    I think this means that the piston area must be faulty. The thing is, it doesn't keep running when not pulling the trigger so it must be making up some kind of pressure I think?

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  81. Hi,

    I just thought I would share my recent experience fixing my K3.80.
    Firstly there is a very useful service manual with fantastic exploded-view diagrams of all the components of all the parts of this washer here:

    http://www.proffia.no/static/Karcher%20deletegning%20K%203.80MD.pdf

    It also lists all the part numbers for each item to help you when ordering spares.

    The problem with mine was a leak from the "FRONT HOUSING MODULAR COMPACT" according to the manual. To you and me that is where the hose from the detergent bottle connects to the pump assembly. The reason it was leaking is because the o-ring on this part had split. I tried numerous regular plumbing o-rings(I am a plumber) but none would fit properly to allow the part to be re-seated in the pump assembly - they were all a bit chunky so I paid a visit to the local Karcher spares place and picked up a new complete part for £8.00.
    Unfortunately I was one of the numpties that managed to empty the oil everywhere in the process off stripping the unit - I didnt find this very useful page until after the event!
    So I also picked up some 15W/40 motor oil. When I refilled the oil I found that I used less than 100ml to get the level to within a cm or 2 of the lip of the motor body. God only knows how some people managed to use an entire litre of oil as the part of the motor that houses the pistons and bearings is itself smaller than 1 cubic litre!

    Anyway, after reassembly my washer is now working an absolute treat. I used it for about an hour last night with no leaks, no nasty noises, and it has some lovely fresh oil to help keep it going strong
    Anyway, this has been a very useful site so thought I would share my experiences in the hope it helps someone else.


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    1. Many thanks for adding this useful detail Christopher. I'm sure that other readers will find this very helpful.

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    2. I have read your blog about Karcher products and found it most interesting. I too had a problem with my Karcher KB3030B leaking water and a little oil. Having worked on on much larger pumps in my working life I set about repairing the aforementioned pump. No obvious external signs of any problems so a complete strip down was called for. On examination the o ring seals appeared OK but were changed any way. Now comes a bigger a problem, I noted the wiring connections down on a piece of scrap paper which has now disappeared, the dog being the main culprit but I have no proof. Could you tell me where I can get a wiring diagram from or does anybody know the colour connections ? Best Regards Howard

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    3. Hi Howard - OMG, Sort that dog out!!! Regrettably, I don't think I can help you with your dilemma. I can only suggest either looking for a YouTube video showing a KB3030B being stripped down, or contact Karcher UK and ask their Tech Dept to assist, (they're usually pretty helpful. Good Luck.

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  82. Hi There,

    This is really embarrassing. I always take photos of things as I dismantle them, but my Karcher 3.575, well it just stopped working and I rather waded into the thing, particularly those lovely deep set Karcher "don't do this, buy another one instead " body screws.

    Turned out a new high pressure outlet was needed - duly ordered, installed and then I stood there holding the detergent hoses thinking "ermm...."

    So, fellow Karcherites, when you finish falling, about would someone please tell me which hose goes to which nipple both inside at the base of the unit and outside at the the detergent regulator knob - coz the last thing I am going to do is put it back together and then have to take it apart again as the drive fills with bubbles or something.

    Ta.

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  83. Hi there,

    This is really embarrassing.

    So I'm standing on the drive and the Karcher K3.575 keeps spitting its high pressure hose out like a child who won't eat its brussel sprouts.

    Onto the net, google the problem, need a new high pressure cover. Into the garage, tear the thing to bits, particularly when those Karcher "don't do this, buy a new one from us" deep set screws start to get in the way of progress but importantly DID NOT TAKE PHOTOS - which I always do when dismantling things for the first time.

    Take part number, order new one, new one arrives, fit new one and then find self standing there sayng "ermmm...." with two detergent hoses in hand.

    So, fellow Karcherites, once you've finished falling about laughing, can anyone tell me which hose goes to which nipple inside at the base of the assembly and then where it then goes at the top to attach to which detergent nipple on the addition dial.

    One thing is certain. I will not stand in a drive full of bubbles realising I'm going to have to take it all to bits again!

    Ta!

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    Replies
    1. Not really sure that I can help on this one, other than to suggest going to YouTube and entering your Model/Make number to see if there are any videos showing your model being dismantled and reassembled, (there are a surprisingly large number of videos like this on YouTube!) - other than that, you'd have to wait for another reader to advise, but this probably wouldn't happen very quickly. Best of luck. If you DO resolve it, please post your update for the benefit of any other readers who may suffer the same dilemma.

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  84. Well thank you anyway. I surely will be happy if another reader can advise but as for YouTube, have trawled through it for hours, nothing relative to this simple issue. Have frozen frames to inspect backgrounds - watched videos on other models to see if they would provide a clue. Nothing.
    Tried searching Google for schematics, some show the tubing, none show the actual connections. You seemed the most hopeful site that I found in a lot of searching. Don't know if you're UK based but if so you can understand why I would wholeheartedly support a Haynes manual. Will take an educated guess, see what happens and advise you of result. Will use wife to switch it on
    :)
    Many thanks.

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  85. Hi, I recently bought a second hand Karcher K2.94M, It works great for about 15 minutes then stops working :( There's a buzzing noise when I press the trigger as if it is trying to fire up but doesn't. If you leave it for a couple of hours it works again for another 15 minutes or so. I'm thinking maybe a bad capacitor?? Any suggestions would be greatly appreciated

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    1. Oooooh - Not had this one before on the blog!!! Can anyone out there help shed any light on what might be causing this? The nearest answer I can find on the web is at http://forums.moneysavingexpert.com/showthread.php?t=3478031 (Copy and paste link into your web browser). Sorry I can't be of more help.

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    2. Thanks for the speedy reply. Yes that sounds exactly the same problem I'm having. I can get a new capacitor delivered for about £4.50 but not sure if it's worth trying as it didn't seem to fix the one in that link. I might strip it down first and have a look at the pressure switch as mentioned also check the capacitor for any visual damage. Thanks again :) I'll let you know how I get on

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    3. You're welcome - Always worth having a go at repair as long as the cost of replacement components doesn't come anywhere close to exceeding the likely value of the machine. Keep us all posted & good luck!

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  86. Hi my karcher 520m had water pressure left in it from the last time it was used, now the motor runs continuously but has no pressure power . Inlet outlet clear. There is no water leaking from motor

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  87. Hi....This is a very helpful blog. I'm been trying to resolve an issue with my K5.700 which had suddenly started running at only 1/2 the normal pressure. I've stripped it down and can't see anything wrong with the valves, no cracks or leaks. The piston chamber had only what appeared to be a white grease in it. Having read this blog, I've realised that it was obviously oil at one time, which had now been mixed with water. I've renewed the 3 piston seals but I'm not sure how the water has got in there other than through the seals.

    When I initially connect every thing up and switch the water on, the first pull of the trigger appears to work around 90% of the correct pressure but as soon as I let go of the trigger and then pull it on again, it just runs at about 50% pressure and the motor doesn't stop when I let go of the trigger either, although it's not pulsating. If I turn the water off at the tap whilst holding the trigger on and leaving the motor running for about 30 secs and then turn the tap on again, it will again fire up to about 90% of the normal pressure but as soon as I let go of the trigger and then pull it on again, it runs at 1/2 power.

    I'm guessing that it's the control head but there are 2 on this model and at about £50 each, I'd like to have a warm feeling that this would solve the issue. There's also a bypass valve on the control head. I've taken it out and it appears to depress okay but I'm not sure what the symptom would be if this didn't work correctly.

    Has anyone had a similar problem? I would appreciate anyones thoughts on the issue.

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  88. Hi Phillip, - K5.700 is not one that I'm familiar with, but I did notice that this model has a 'safety valve' to avoid over pressure. I'm wondering if it's this feature that may be causing the problem, although I can't see this feature on the 'exploded diagrams' at http://www.ransomspares.co.uk/parts/search/switch/karcher/pressure-washer-spares/k5.700%20eu%20(1.181-300.0)/b/c/m/ Hopefully some other user may have the answer for you. I do hope so, and I hope you get to the bottom of it.
    If you DO manage to resolve the problem, please feel free to update the results on this blog, for the benefit of other users. Good luck.

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  89. Hello. I had this issue of motor running and no pressure. I have stripped a k5.800 eco and found the white valves are definitely the cause of the issue. However the black pump housing does not just pull out. So I cannot access to replace them. There are no bolts remaining to remove. Videos have been watched and it should be easy?
    Anyone have any advice?

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    1. If your valves are like the K5.700, 3 of the valves appear to be moulded in the housing and I don't think you can just replace them without replacing the complete pump assembly. The 3 valves in the smaller triangular area do just pull out and you can get replacements for them.

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  90. Hi Smugdane.....Having found this you tube video (unfortunately not in English) https://youtu.be/cX7iGzMo3V8.....I could see that he had the same symptoms as I did. I took the pump apart again, pulled out all the valves in the top assembly and cleaned them all up, re-assembled it again but still had the same problem. I bit the bullet in the end and bought the new assembly that comes complete with the bypass valve. Having fitted the new part, it now works fine. I've no idea what is wrong with the original part as I can't see any cracks and the valves appear to operate okay but at least it's going again.

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    1. Hi Phillip - Thank you very much for providing some very valuable feedback. Your experience is a bit of a mystery, but at least you now have a working washer again. It just shows that DIY can have benefits. Cheers

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  91. Hello, I have a K3.575 that is leaking badly from the small detergent elbow valve as it popped out the o ring (seal). I re fit it and was fine for 15 minutes then the same happened this time splitting the seal. Could it just of been a weak seal? Has anyone come across this before? Should I just try a new seal or a new detergent valve. Any help will be very much appreciated

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  92. Hi, I have a Karcher 411a washer which runs ok but failed to switch off when the lance was not in use bursting the delivery hose I suspect the spill valve/pressure switch are they simple to remove,clean & replace?

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    1. Hi Anonymous - What you say sounds logical. Personally I haven't changed anything like this, so I can't comment, but it surely can't be too difficult to do if you get a replacement part. There is a YouTube video showing how to replace this part at https://www.youtube.com/watch?v=OZBlkLxHy6k (copy & paste link into your browser). Sorry I can't help further.

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  93. hi, I have a Karcher 5.7 pressure washer which has started developing a fault when I tried to use it for the first time this year. The main problem is that the motor keeps cutting out during use, but even when it's working the pressure seems to be quite a bit lower than I expect. I've checked the water supply pressure and the electrical supply, fuse etc and all seems fine so it sounds like it's something more serious that requires an internal inspection? Any advice on where to start will be much appreciated.

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    1. Hi Anonymous - Unfortunately I'm not familiar with the 5.7 so I can't really give any useful advice other than to check out if there's any helpful video on YouTube. Just enter 5.7 on the YouTube site and see what you get. The only other 'easy' check, before taking your machine apart, is I notice this model has a 'fine water filter' fitted. Have you checked that this is clear of debris? Sorry I can't help more, but it's probably something dead simple, so I hope you get it going again. Good luck.

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    2. Hi Smugdane, Thanks for the advice. Just so that it may be of benefit to others with similar issues I though I should share the progress. After further investigation and research I found out that the symptoms of cutting out during use could be caused by air lock so to remedy this, I disconnected the power supply, connected the garden hose to the inlet and removed the high pressure hose and trigger. I then let the water run through for about 5 mins and reconnected everything and tried the machine. I'm pleased to say that it's now working fine. I'll see if it continues working when I next use it for extended period.

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    3. Excellent result... thank you so much for posting an update for the benefit of other readers. I sincerely hope that this HAS solved your problem.

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  94. Hi. Came across your blog whilst searching for answers to pressure loss on a k2. I decided to strip the motor and pump down after seeing the state of your pistons and as pleasantly suprised to see metal pistons in there. Only problem then was, what was causing the pressure loss? After removing the motor from the gearbox i found my answer. The nylon cogs that transfer drive from the motor to the gearbox had disintegrated leaving bits every where inside the housing. The espares website mentioned above doesnt seem to supply them. Do you know of any other karcher spares sites or any one that might be able to help source this part? Great blog

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    1. Hi - There are quite a number of spares suppliers such as ransomspares and pressure parts http://www.pressureparts.com/ownersmanualsk1.aspx/
      Sometimes these companies don't always seem to list the part that you're looking for, but a phone call often brings results. Failing all the usual on-line spares suppliers, (and probably as a last resort), you can always phone Karcher UK who also sell spares! - Good luck

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