Karcher pressure washer help!!!!!

sam375(PA)July 18, 2005


I have a lightly used 2 year old gas 2400 psi model 2400hh Karcher pressure washer. Honda engine.

It runs but water comes out of it as if it is just a hose and no pressure.

Last year the pressure would go in and out and this year nothing.

Garden hose and house water pressure fine. No leaks also. I want to take it apart and try some things to fix it myself but I don't even know where to begin or have a good diagram to go off of. Instructions are not good, and it was NOT wintered in the cold. What is the pump spray I seen online at sears.com for? Called Karcher and did the 2 things they said.

Any help would be greatly appreciated.

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canguy(British Columbia)

Sounds like the unloader is crudded up with mineral deposits and stuck open.

    Bookmark   July 18, 2005 at 9:52PM
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Where is the unloader and how do I fix it?

    Bookmark   July 21, 2005 at 8:41AM
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I had the same problem ... look for a black plastic cover with a silver snap on top; pry off the silver snap and lift off the plastic cover; next remove the two screws on the top plate then pull out the piston inside - if unable to lift out, start unit and watch it pop out - coat piston with lithium grease and reinstall - it will work great!

    Bookmark   July 28, 2005 at 2:57PM
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hope u didnt use clorox in it. its a killer of brass fittings

    Bookmark   July 28, 2005 at 8:01PM
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stevejd235(z4 MN)

Did the suggestion from "tommyw" work for you? Any updates?

    Bookmark   August 8, 2005 at 12:59PM
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I just had eye surgery, will work on it in a few weeks and I will be sure to post then-
Thanks for all your help!

    Bookmark   August 8, 2005 at 1:27PM
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You must store in a location that doesn't freeze, i.e., last winter. If you left the unit in a shed during the winter and you live where there is freezing weather, death to you power washer is likely.

    Bookmark   August 11, 2005 at 9:35PM
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stevejd235(z4 MN)

Did you ever get a chance to try "tommyw" suggestion? I attempted this past weekend to get the "silver snap" off of the black plastic cover but it would not come off. I did not want to force it too much. Just curious, thanks...

    Bookmark   September 6, 2005 at 8:37AM
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stevejd235(z4 MN)

Finally found time to try "tommyw" suggestion and it worked perfectly. If you pry off the silver cap, remove the black cover, use an allen wrench to remove the two "star" screws (or you can remove the four engine mounts and remove the whole engine), lift out the white plastic part with the brass needle & spring, finally lift out the stainless steel piston or like I had to start up the engine (make sure you have the water hooked up and running) and watch the piston be shoot out (I placed a towel over the piston before starting the engine). Then you can put white lithium grease all over the piston and reassemble.

Thank for suggestions in this thread and the personal emails.

    Bookmark   September 19, 2005 at 8:16AM
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If you run bleach thru any pressure washer, run clean water thru the chemical pickup as soon as your done or you will be replacing the chemical pickup very soon.

    Bookmark   September 20, 2005 at 3:50PM
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aesanders(8b Alachua, FL)


You stated that storing a pressure waasher outdoor's in winter will kill them. Do you know what happens to them, and is there a way you can winterize it so you could store it in the cold?
I was planning on keeping the washer I got over the summer in the shed, but not sure now.


    Bookmark   September 21, 2005 at 4:24PM
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The water freezes,and cracks whatever it's inside of...........

    Bookmark   October 26, 2005 at 12:03AM
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The silver cap is a press on type, just pry it straight up. The service center wanted to charge $80 for just this fix, said it takes 45 mins. to do. I did it in less than 5. I used a star bit#27 to get the 2 bolts out, had to start the thing to get the unloader out and used my thumb nail to scrape the white stuff off (not much) and rubbed white litho grease on the unloader, put it back together and it works like new. pressureparts.com has the drawings and parts list for it so you can see what it is before taking it apart, it is really easy. ( they also said to grease it before buying a new one

Here is a link that might be useful: parts drawing

    Bookmark   March 16, 2006 at 3:27PM
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It's taken me awhile, but today I finally got around to taking it apart.
I can not seem to get the "piston" out, eventhough I hooked up the water and started it in order for the piston to shoot out. It has some white build up around it. So far the instructions are perfectly accurate up to this point. Below is a link to the diagram I found. I really appreciate all the help thus far. Any other methods of getting it out so I can clean it and use the whote grease and reassemble would be great!
this is the diagram link look at page 6 http://www.pressureparts.com/mmDEV/PDF/karcherparts/K2400HH-COSTCO%201.194-301.0.pdf

Here is a link that might be useful: Parts diagram

    Bookmark   April 12, 2006 at 4:37PM
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I think I am in trouble. I took the 4 screws off the front and out came the oil. inside are springs and I am assuming pistons. I want to just put it back together now but do I need to put oil back into the area it cam out of or do I put it back together and just poor oil back into the regular area.

    Bookmark   April 18, 2006 at 3:58PM
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Also, what kind of oil should I get?

    Bookmark   April 18, 2006 at 4:05PM
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I have a similar problem with my Karcher K397. it does not seem to have the same power as it used to. can anyone help. Its only 13 months old

    Bookmark   May 3, 2006 at 10:12AM
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Thank you Tommyw!! I have a 2 year old Karcher K2400 and it stopped engaging the high pressure when I pulled the trigger on the wand. I resorted to throttling down and back up again while holding the trigger in the on position to get it to work. I searched the internet and found these posts and pulled out the tools today and it worked. The chrome button pried off with a little work. The black cylindrical plastic cap lifts right off exposing the white plastic housing held on by two star bolts. I used a hex key to unscrew the bolts. You need to hold on to the plastic housing when removing the last bolt because there is a small spring that will launch the housing if not held. Mine popped out when unscrewing the last bolt and the spring and valve(part #9 on the parts diagram)dropped to the ground.
The "piston" (spring valve-part # 12 on the diagram) remained in the housing. You won't be able to pry the "piston" out. I put a rag over the housing, turned on the water and started the motor to get the "piston" out. It will pop up into the rag once the motor is started. I didn't see very much of the white mineral deposits on the piston but wiped it down and greased it up with the white litho grease. I put it all back together and fired it up and it works great now!! It all took me about 15 minutes to complete the job. Thanks to all who provided these posts and help save on costly repairs!!

    Bookmark   May 7, 2006 at 6:00PM
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I have the same problem with my 2400, I winterized it too. First started out with a no start problem, I removed the carb and took it apart and cleand,installed new plug and fresh gas and I got the engine running well. The engine was runnung a little high so I adjusted the governor.
Now my pressure is not there and also when I put the strongest
spray adapter on it has a delay,maybe three seconds than it kick in,sometimes longer.
I took the screen filter off and cleaned the inlet,I inspected the gun and cleaned. I took off the four bolts in front and took apart the brass pump because I notice a very small drip. I lost a bit of pump oil myself so I refilled the loss with comressor pump oil. I will try that pressure valve next. More problems than I expected from Karcher,my Northern Tool brand power washer with the techusea engine was trouble free for many years. Go figure...

    Bookmark   May 25, 2006 at 12:06AM
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Ok today I took apart that pressure valve you guys are talking about.I cleand all parts and installed a silicone grease I use on all machinery. This was great results, by far the only thing I did that made a substancial difference. The machine works well now with no ill effects after taken the pump competely apart. Thanks for all the information.

    Bookmark   May 25, 2006 at 9:19PM
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I am having the same problems with a K2400HH. I have no high pressure. I took the unloader apart and cleaned eveything up ( alittle rust but no mineral deposits). I now have something that resembles high pressure. High pressure goes in and out, in and out. It only lasts for a second. DO you think I need to clean the unloader better or apply more grease? Any help is appreciated.

    Bookmark   May 27, 2006 at 11:26AM
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Take it apart again clean all parts very well, also clean the cylinder hole itself. clean the film off it and reassemble using a good grease.I use clear silicon.

Make sure you are reassemble the parts the right way

    Bookmark   May 27, 2006 at 3:47PM
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I have cleaned the hole with a piece scotchbrite and lubed with moly-litium grease. No help.

    Bookmark   May 27, 2006 at 5:15PM
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dkeener(Z7 NC)

I had the same problem with a Coleman and unloader valve cleaning and Lubing didnt help. Turned out that the spray nozzle was slightly clogged which turned out to be the cause. Cleaning it out good solved the problem.

    Bookmark   May 27, 2006 at 5:59PM
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Just an additional note, the stuff in a pressurized can that SEARS sells to pickle your pressure washer over the winter is half Propolyne Glycol (RV antifreeze, harmless to rubber) and half mineral oil. I pour this solution into a piece of garden hose attached to the pressure washer inlet and then pressurize it with about 30 to 40 PSI from an air compressor hose to force it into the pump that has been emptied of water previously. Give the engine a few pulls without the plug wire attached and it usually lubricates and preserves the pump over the cold winter. I read the ingredients on a can of preservative I bought from SEARS for 10 dollars. Brought it back and went to Walmart, spent 4.28$ on the other supplies listed and have used it for the last 3 years. Hope this information helps you care for your pressure washer pump.

Just a note, This mixture would most likely prevent your pump from freezing and damaging it, but I still keep my pressure washer in a cold basement that does not get below freezing. just want to be safe. .. New pump is a couple of hundred dollars or more.

Regards, Pag

    Bookmark   June 2, 2006 at 11:29AM
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The front attachment of my Karcher 9020 pressure washer's broken where the hose attaches. I've purchased a replacement part but the hexagon screws on the back of the washer are proving a real problem.
Can anybody advise what tool to use? I've seen some hexagon-headed tools for sale but I need to know the size of the screw and many allen keys are too short for the task.

    Bookmark   June 2, 2006 at 12:18PM
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My Karcher 2400 HH would not maintain constant pressure after releasing gun trigger. I would remove the nozzle, press the trigger allowing water to flow, replace nozzle and it would again pressure spray. This would happen every time I would release the trigger on the spray gun. Karcher's web site trouble shooting guide stated that the washer would need to be repaired at a service center. As per the above instructions, I performed removal, cleaning and regreasing using a good quality water proof grease and reassembled. This took maybe 10 minutes and the washer now performs without flaw. Called the local service center and they charge $65 to perform the repair. Thanks, this has been a most helpful forum.

    Bookmark   June 12, 2006 at 9:57AM
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I have a similar problem on my Karcher HD3101DR pressure washer. Engine starts up fine, but upon releasing the gun trigger, I get high pressure for a fraction of a second followed by water flow that appears like normal garden hose pressure rather than the high pressure I expect.

The parts list for this model is hard to find. I obtained a hard copy from a dealer. I see that the pump is identical to that on the HD3000 series models. You can find the parts manual for the HD3000 series at http://pressureparts.com/OwnersManualsK1.aspx . Could someone please point out where the unloader is on this model? Thanks

    Bookmark   August 6, 2006 at 8:24PM
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I had the same problem with the unloader and took it apart and greased it and reassembled it. Now my 2400 goes from high pressure to low pressure every 4 or 5 seconds while holding the trigger constantly. If I cut back the power on the engine to a little less than half throtte it stays on high pressure but the engine is lugging almost to the point of quitting. The greasing of the unloader took care of one problem.
Any suggestions

    Bookmark   March 25, 2007 at 6:11PM
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Mine went bye bye, since I was never able to repair it and of course the karcher repair center gave me ahigh estimate. I bought a high psi electric one and surprisingly it works just as well as the expensive gas.
Good luck

    Bookmark   March 25, 2007 at 6:43PM
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I did the unloader repair today and was hoping for the best. Not sure how much grease to put on the piston. I just put a light coating on it--maybe I should have lathered it up.

Anyway, I have the same problem "mlthorn" has. My pressure washer will lose pressure for a few seconds and then kick in again at full pressure. This happens several times for the first few minutes of operation and then it seems to be fine.
Is that just the nature of the Karcher pressure washer or am I doing something wrong? The pressure washer is only a few months old and I have only used it three times.

Thanks, Brad

    Bookmark   April 1, 2007 at 11:30PM
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thanks tommyw, your advice on fixing the stuck unloader valve on the karcher preasure washer saved me some bucks and frustration.!

    Bookmark   September 12, 2007 at 12:17PM
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Does anyone know where I can buy parts for an electric Karcher 395. I have one that worked alright until someone broke the plastic fitting the water hose attaches to.

    Bookmark   September 20, 2007 at 4:33PM
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I also would like to express my gratitude to tommyw for his advice to remove and grease the piston, a.k.a. spill valve on the Karcher 2400HH power washer. Rather than using white lithium grease, I used waterproof plumbers grease which was recommended by the helpful technician at pressureparts.com. To view pictures of the removal/greasing of the valve, click on the link below. My successful "surgery" of the valve, followed the unnecessary replacement of the pressure hose, gun and pressure tips in my efforts to narrow down the problem of no pressure. Karcher's manual and tech support were of absolutely no value. After learning of the number of other identical complaints, I am shocked that Karcher does not suggest the greasing of the valve. Again, kudos to tommyw for him saving me and many others the cost of a service repair. I intend to express my dissatisfaction to Karcher corporate in hopes of better tech support. I encourage others to do the same at the following address: Karcher Technical Department Manager, 2825 Breckinridge Blvd. Suite 120, Deluth GA 30096

Here is a link that might be useful: Image view for removal of the Karcher 2400HH spill valve

    Bookmark   September 29, 2007 at 8:45AM
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hi all,
i read all information in here very interresting help full , and try to the unload vaul my sefl , because i have same problem no pressure , but i realy don't where i can get the LITHIUM GREASE so please help me !!!where i can buy that LOCAL or ONLINE.thank you so much to all!

    Bookmark   February 4, 2008 at 10:09AM
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If it is not too late, remember to store where it is protected from freezing. I see way back someone asked me about what breaks...can't say I remember, but it was a small part in my case of an electric Karcher unit. I corresponded with Karcher and they sent me both a pump break down and a part to repair. They may not do that any more, they made no money on the unit they sold me. The is all at least four or five years ago, the only reason I post here is to remind all to protect from freezing.

    Bookmark   February 4, 2008 at 11:11AM
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The sticking pressure relief valve is somewhat common with the Karcher 2400HH series pressure washer, it is caused by hard water and lack of grease on the pressure relief valve. To remedy the problem, use silicone (plumbers) grease to lube the o-rings on the unloader valve part# 4591040 (karcher calls it a spill valve on the parts list) You can click on the link below for more help. A helpful note, if you store your pressure washer for long periods of time, than you should draw anti-freeze into the pump for storage... make a short 2' garden hose and connect it to the inlet of the pump, with a funnel stuffed into the end, poor anti-freeze into the hose and start the engine, this will draw the solution into the pump and protect it from corrosion and keep all internal parts lubricated (plus keep the pump from freezing)

Here is a link that might be useful: Pictures of the Karcher 2400HH Spill Valve

    Bookmark   February 8, 2008 at 2:07AM
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What do you do if you have tried all the above and your valve it still stuck? Well, don't take out the front four bolts thinking you will have access to the valve from a different vantage point. Karcher has a new valve module that is resistant to oxidation build-up. It is costly. It cost me $185.00 to rebuild my Karcher 2400HH. Is it worth it? Depends how much you like your Karcher? If you are going to take this project on, you better be a good handyman and have some patience. I did it so it is not impossible for a consumer. Good luck Bob

    Bookmark   April 16, 2008 at 1:05PM
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Just a follow-up to my message above. You could keep the cost down to about $137.00 (includes shipping of the new valve) if you re-use your original parts. I got talked into $50.00 worth of additional parts. O rings, micro valves etc. Not as difficult as it sounds. Once you get the parts, about an hour and a half worth of work. If you do take out the four bolts, which you have to do in order to repair it, have it facing upward, otherwise oil all over the place.

    Bookmark   April 16, 2008 at 1:30PM
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I have the exact same pressure washer now with a great running engine with a blown pump (ran bleach in it and didn't rinse it like an idiot). Would it be possible to replace the POS pump with a CAT/COMET commercial quality pump unit as a bolt-on replacement?

    Bookmark   April 16, 2008 at 7:43PM
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I just followed the Tommyw advice and took mine apart. I could NOT remove the piston. I had the water running and the motor on but the piston never came out. Is there a trick to it? Can i force it out somehow? I'm guessing this is a major part of my problem. Also my hose was dirty which caused this entire problem and i think it gummed up the insides. I took a picture, please advise!

Here is a link that might be useful:

    Bookmark   May 18, 2008 at 4:32PM
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i'm gussing that might help. but i'm more concerned about the water leaking out of the unit (as you can see in the pictures) and the face that the piston did not "pop" out.

Here is a link that might be useful:

    Bookmark   May 18, 2008 at 4:36PM
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ok so i got everything removed, cleaned up the insides, cleaned the filter, put lithium grease on all the parts and slapped it back togther. Now i notice that the white plastic piece that the screws go through is leaking water out of two oem pin holes on top of it and spraying out. MY pressure is about 1/10 of where it should be. Anyone have an idea of whats wrong or what to do next?

    Bookmark   May 19, 2008 at 6:52PM
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just wanted to update everyone i put the unit together wrong after again looking at the schematics. I put it all together one more time and removed all the grease off of the sprint and pin, and everything works great!! Also you guys know to wash out the plastic filter? I think that made a major difference for me as well. The filter in inside the house inlet...

    Bookmark   May 21, 2008 at 4:25PM
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I have pressure problems with pressure washer which is the same model as the one we are talking about here, i did all of what you guys has said in here, but no luck. I checked the oil and it looks like a creamy marroon staind, not like your typical oil, so i think water is getting into the engine somehow. How do i solve that problem? and looks like there is some standing water in the filter part.

    Bookmark   May 27, 2008 at 12:59PM
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Single use pressure washer.
I bought a Karcher 395 two years ago. Used once the day I bought it. I was stored in the garage never frozen, or mistreated. Last year my in the spring I did not used it, since next door steve pressure washed my driveway as a gift. this year, Steve not around I took out my karcher 395. tried to get it started, water sprays and leaks from all over the the pump. Out of the nozzle, there is no pressure, actually that is the only place water does not come out of. Is this stuff made In china too?
Extremely dissapointed, and never a karcher owner again!!!!

    Bookmark   June 1, 2008 at 5:30PM
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Karcher HDS 400 C Hot water pressure washer (fuel oil/diesel).
Fires up hard. Smokes. Rumbles. Won't keep burning.
Is the photocell/electronic eye dirty? Is the solenoid bad? What do I take apart to check and exactly how?

    Bookmark   June 7, 2008 at 2:17PM
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I own a Karcher 2400HH pressure washer. It's three years old and last year I had problems with high pressure. I cleaned and lubed the unloader valve and it worked great. Two weeks ago I brought it up from my basement and tried to use it. I had high pressure when I squeezed the trigger but when I released the trigger handle, the high pressure was gone. I have cleaned and lubed the unloader valve several times within these last 2 weeks with no avail. Occasionally high pressure returns when I change a tip but again when I release the trigger the high pressure is gone. I cleaned the trigger handle hose and fittings but I still have high pressure problems. I have concluded that with so many people having the same problem this 2400hh pressure washer was not made very well by Karcher. This lemon of a pressure washer is not worth the aggravation. I will be purchasing an electric pressure washer from another company shortly. They are lighter, easier to store and have enough power to do most of the jobs around your home.

    Bookmark   June 20, 2008 at 11:56PM
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I have a Karcher 395 with a broken hose inlet. I have purchased a new part but am having a problem with dis-assembly. What type of head is on the fasteners?

    Bookmark   July 3, 2008 at 6:34PM
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Could someone tell me where the unloader or spill valve is located on the Karcher 3101 model? It has been used very little and now develops no pressure.

    Bookmark   July 6, 2008 at 9:26PM
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I have tried all of the above suggestions. I've rebuilt the pump once with parts ordered through the catalog. I'm on my second trigger gun. I've decided to pull the motor out and make a small mini bike for my nephew. Any one have suggestions for plans on building a mini bike/ go kart?

    Bookmark   October 28, 2008 at 8:22PM
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I am going thru a mod g4000sh and the parts drawing is about as helpful as a poke in the eye with a sharp stick. it has no high pressure and so far the only piece i have found that has a blown o-ring in side is a p/n 45803230 .can anyone tell me if this could be the culprit?

    Bookmark   November 10, 2008 at 10:26PM
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Here is where you can purchase the plastic inlet to the K395 pressure washer

Here is a link that might be useful: Karcher K395 Garden Hose Replacement Part

    Bookmark   December 28, 2008 at 7:47AM
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I have a Karcher 2400HH. I removed the 4 bolts that hold the pressure pump and all the oil leaked out. The oil was milky in color. Does this mean that water was mixed in with the oil? Im going to install a repair kit to solve the water in oil problem. Here is my question, how do I get the oil in as there isn't a drain or fill port? What type of oil is required and how much will it require.

Any assistance is appreciated.

    Bookmark   March 8, 2009 at 5:45PM
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Here's a link to Karcher looks like you need to use 15w-40 oil fill with 100ml or 3.38oz.

Here is a link that might be useful: Karcher oil fill guide

    Bookmark   March 15, 2009 at 8:58AM
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model HD 3101...Where is the unloader valve located on this unit??? Is it under the pressure adjustment valve? Any help will be appreciated. I am diving in now!

    Bookmark   March 18, 2009 at 12:45PM
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Karcher......what else! G2500lh, Worked great for 4 months, sat a weekend. When i release the trigger the pressure will not drop off. The pressure stays pumped up, loading the engine down almost to killing it from "lugging" it down. lower than normal pressure when spraying. Leaking from the top of the unloader valve from under the plastic cap (cover held in by single silver pin.) Pulled apart , cleaned/ lubed) AUGHHHHHHHHHHHHHHH!!!! (calmly.....help)

    Bookmark   March 20, 2009 at 10:05PM
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I just experienced this with my in-laws K 2400HH. I cleaned it three times and greased it, but it didn't help.

I bought a new valve and the repair guy gave me some light file paper and burnishing rag. I cleaned out a lot of the gunk on the inside of the cylinder, and then cleaned it with electrical cleaner.

He also gave me a dime sized of some sort of orange grease which he said would help keep the minerals from depositing. It was MUCH better than the white lithium spray grease.

I greased the cylinder, the new valve (that was $27), and re-assembled it. Problem solved.

He did note that after you shut off the engine, run water through the wand for awhile to help the pump cool down.

    Bookmark   April 8, 2009 at 10:13PM
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I also have the g4000sh pump and have no pressure. Can anyone tell me if it has the uperloader valave like the 2400 and where it might be ? thank you for the help.

    Bookmark   May 9, 2009 at 8:58AM
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I cleaned and lubed the unloader valve like described, but it still sticks open. I have a Karcher G 2330 LT. The cylinder looked clean. Any suggestions?

    Bookmark   May 12, 2009 at 12:36PM
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Just fixed my HD3101 that had issue with high pressure kicking in/out every 3 secs. The spool/unloader valve is located where you regulate the pressure. Just pop off the knob and unscrew the stem then remove the sleeve (piece between stem and valve) then pull out the spool valve/unloader. It looks just like what is in the pictures of the other pumps listed above.

I used synthetic grease for wet applications and greased both the valve, sleeve, stem and bore. I also went ahead and cleaned the filter screen on inlet and ran gun without tip the remove any trash in it and made sure no blockage in the tips..works perfect now

    Bookmark   May 24, 2009 at 4:28PM
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My Karcher 2200G has no pressure at all. The engine starts fine, but the pressure is worse than the water hose itself. I have disassembled all the hoses and have narrowed the problem down to the main unit. I took off the cap, white housing etc., but the piston will not come out. I started the motor with the water running and the piston is stuck. Water comes out of the area around the piston but it did not pop out as it should. Where do I go from here. Help. Can I still spray the lithium grease up around the piston?

    Bookmark   May 24, 2009 at 5:13PM
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Can you get a vise grip pliers on the hex head of the valve and pull it out? Sounds like its stuck pretty good. Make sure that you are indeed on the correct part also, hate to see another problem arise.

    Bookmark   May 24, 2009 at 8:29PM
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Found this string and was hoping for some other ideas. I pulled apart and lubed the unloader valve per the instructions above but it didn't fix my problem. When i release the trigger the pressure will not drop off and water comes flowing out the unloader - the engine bogs down and almost stalls - I end up having to shut it off. Any ideas what might be the problem???

Thanks in advance.

    Bookmark   May 30, 2009 at 9:00PM
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Like some of the others who have posted to this forum, I am having problems with my unit. My story follows:

I have a slightly used K 2400 HH Karcher washer. I keep it in a warm garage when I am not using it. Last January, I took it to the church bike shop to clean up some bikes to be repaired. I hooked up the garden hose and filled it with water. Then I hooked that up to the washer and turned it on. I started the machine and began to use it noticing that it seemed to be running a little rough. After an interruption, I shut it down and did a few other tasks, then returned to restart the machine. This time it ran really rough, like it was under a heavy load. Soon it stopped running completely.

I disconnected the water supply and made sure the water line was okay. Then I hooked it back up and tried to start it. This time, it acted like the whole unit was locked. The pull cord would not move on the Honda engine.

Service shops are not close, and Karcher won't answer a phone inquiry. The on line folks claim it is a motor problem. Having had experience with Honda engines before, I tend to disbelieve their motor problem claim.

Has anyone with this forum ever experienced a similar problem with a Karcher washer? Could this all be related to the unloader problem listed in this forum?

    Bookmark   June 2, 2009 at 2:36PM
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To everyone who cannot get the piston out of the unloader because it is stuck, even after hooking up the water, you also hooked up the powerwasher hose and gun, right?

I had the same problem with no high pressure and followed the above directions to lube up the piston and now it works like new. At first, I removed the cap, hooked up the water, put a rag on top and started the motor but the piston did not move. I forgot to hook up the gun and when I did and restarted the motor, *POP* out came the piston. Just an FYI because I didn't see it specifically mentioned above.


    Bookmark   June 5, 2009 at 1:51PM
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I have an electric Karcher Pressure Washer, which lost it's pressure and leaks lots of water through the pistol. Item is used only 2 or three times last summer, after I bought it to replace another one having the same problem. I never use chemicals or anything.
Any suggestions on how to solve this problem??

Thank you,

    Bookmark   June 15, 2009 at 3:00PM
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where exactly is this black plastic cover with a silver snap on it, i've looked everywhere and have yet to find it?

    Bookmark   June 23, 2009 at 10:32PM
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I have a Karcher 3050 HO that has low output pressure. Worked fine last year, loaned it to the kids and it came back this way. I have checked the input hose connection and filter, perfect. My guess is the pressure is less than half of what it should be. Any help out there? Can the pump get damaged if the kids ran it without pressurized water on the input? If the pump is shot, where can I find a rebuilt one, a new one sounds too expensive. Have tried over a half hour to find anything from Karcher, they must run and hide soon as they sell a unit. Not pleased. Someone help this Oregon Duck.

    Bookmark   June 24, 2009 at 8:01PM
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I have a Karcher KB9030 that I have only used a couple of times since new.

The hose has started blowing out when the motor is running.

The male and female parts of the connection to the main body are plastic, and there are signs of thread stripping.

I have phoned Karcher and they are unhelpful.

I am thinking about using some sealant on the threads, as sending it back for repair would be impractical as well as expensive.

I appreciate that this would lock the hose on, and I would appreciate any advice on this matter.

Perhaps someone else has had this thread stripping.

    Bookmark   June 30, 2009 at 11:53AM
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My karcher runs about 20 minutes & quits. I have plenty of pressure, but I have to wait about 10 minutes to restart and go through it all again. Any help?

    Bookmark   August 14, 2009 at 12:17AM
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My karcher runs about 20 minutes with plenty of pressure,
but quits & I have to wait about 10 minutes to restart & go through it all again. Any help?

    Bookmark   August 14, 2009 at 12:22AM
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Karcher K 2400 hh pump not working right. After pump rebuild kit does same symptoms. Motor is off and water is on from hose it will bleed through pressure relief valve on top. When running will labor and push water through pressure relief valve until trigger on wand is pulled. All those valves and parts where replaced. What gives ?

    Bookmark   August 15, 2009 at 11:33AM
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Have a model2300IB The valve in the handle seems to be sticking. Good pressure out of pump but no high pressure out of wand. There is a pin that sticks out of valve that seems to be stuck inside the valve. The plastic handle is supposed to push this pin in and I think it is supposed to spring back out on its own. Any ideas here?

    Bookmark   August 21, 2009 at 11:32AM
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I have a model G3050OH that, I believe, has a trigger gun problem. The water supply and pressure is more than adequate but when I pull the trigger, no matter what nozzel, no water it takes several pulls of the trigger to get the water flowing. The water flow and pressure are fine until you release the trigger then I have to go through the same process of pull, release, pull, release and eventually I get water and pressure.


    Bookmark   August 23, 2009 at 11:05AM
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I have the same lose of high pressure problem with my Karcher G 2600 VH. It appears to have the same pump setup as the 24000 HH highlighted above. Has anyone experienced the same issues with the G 2600 VH? Will the same metohod related to unloader valve removal, cleaning, and greasing apply?

    Bookmark   August 23, 2009 at 11:14AM
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As most know Karcher information is really scarce when you buy the pressure washer and the website is the same. After running several searches I found this site that has most of the pump diagrams and part numbers you might need. http://www.rjbowers.com/xcart/product.php?productid=601&cat=106&page=1

    Bookmark   August 23, 2009 at 12:28PM
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---Just need O-rings

Anyone know where you can buy just the o-rings for the unloader valve and related parts- seems like they want to sell you - $50 worh of parts that you do not need?
Thank Much, Albert

    Bookmark   August 25, 2009 at 1:09PM
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After 3 years of dealing with a tempormental K2400 Karcher with Honda motor found this forum today and performed the clean and lube of the spill valve. 100% improvement using the green tip, but the red, white, orange, and blaster nozzle still don't function correctly. The red one will sometimes work, but the others either don't build any pressure or build and only hold for a few seconds then the pressure drops off, builds again, and repeats like that. Any ideas?

    Bookmark   March 28, 2010 at 3:03PM
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I have the 2400 Karcher, a couple of years old, with little use. No pressure, just faucet flow. I have done what is written in other notes to clean the little piston in the valve as described by others, but on mine, the piston won't come out. Yes, I had the gun installed, hoses installed and the water running, but the piston still does not pop out under pressure. I suspect it is really scaled up. I also cannot get my small vice grips on it because of the metal frame brace directly above it. I can get a small pliers (almost needle nose) on it, but although I can turn it in circles, I cannot pull it out - pliers slip off the hardened slick steel. I will try again today, since I know from all the writing that it is suppose to come out. Thanks for all the advise.


    Bookmark   May 2, 2010 at 7:51AM
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So I garbage picked this what looks to be near new Karcher 2400 powerwasher. Had trouble with engine which i fixed. Hooked it all up to water, fired it up and it doesn't keep good consistent pressure. Took the unloader out and it looks real clean. My question is about the hose. Everything seems to screw on fine but on one end the hose is still loose in the coupling (i can wiggle the end around when coupling is tight) and leaks like a sieve. The o-rings and threads seem fine and I can't tighten the coupling any tighter. I assume it's not suppose to leak like this. Do i need a new hose/hose ends?


    Bookmark   May 8, 2010 at 12:48PM
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I would like to thank everybody who has contributed to this posting. I have a Karcher 2400 pressure washer that stopped building up pressure a couple years ago. I called the local Karcher Authorized and Certified Repair Center (Taft Power Equipment, in Holyoke, MA) at that time. They told me, in no uncertain terms, that my pressure washer either could not be repaired or was not worth repairing. Why would Karcher have a company like this befouling their name? Anyway, about a week ago I decided to list the pressure washer on craigslist. I priced it at $50.00 and said that it was for parts. When several people contacted me immediately and wanted to buy the machine, I suspected that they knew something that I didn't know. I did a search and found this forum. I followed the instructions, and now my pressure washer is like new again. Thanks!

    Bookmark   May 9, 2010 at 2:48PM
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Karcher K 395 M (Electric 1500 psi)

I purchased this unit about 6 years ago from Costco and have been pleased with its performance. I'd never owned or used a pressure washer previously, so I had no true way to judge its power. Several years ago I began noticing some dripping from where I attached the hose. No big deal. Last week I was using it for the first time in over a year and about 45 minutes into use began hearing water hissing from within the motor housing and noticed a little bit of water spraying out. I figured I'd probably have to replace some gaskets/seals (or something). Then about 5 minutes later the GFCI tripped and the unit shutoff. I reset and it immediately shutoff again.

I opened the housing and removed the power unit. I opened the sealed plastic electrical box and did not see any water. I reattached hose and power and again it immediately shutoff. With the motor assembly standing upright on the base of the motor, I did notice a little bit of water dripping out of a large black rubber seal toward the top (I took photos). This was while it was not powered on and therefore not pressurized.

I'm assuming that replacing some gaskets and/or seals might solve this problem, but now there is the additional problem of "electrical" wherein the GFCI is constantly tripping. The switches inside the plastic electrical box appear to be working fine, but I'm not certain (I believe they are labeled as "10 - SCHALTER 16A 3/4HF / SWITCH / INTERRUPTEUR 9.085-034.0" and "11 - MOTORSCHUTZSCHALTER / MOTOR PROT. SWITCH / RELAIS (MOTEUR) 9.085-032.0" on one diagram I was able to download).

I've worked on motors before, but I am by no means an expert. I'm OK with electrical, but understand things as a bunch of "black boxes" and do OK when I have to simply replace one of the "black boxes" (i.e., parts 10 or 11 above). My neighbor is an electrician so I could get help if I needed to test further.

The reason I asking for assistance is because my first reaction was to simply replace the unit, figuring I'd gotten 6 years of reasonable use from it, however I could not find a comparable unit anywhere. I tried over 10 stores and leaned that only a couple currently carries Karcher. I purchased a different Karcher (which cost more than this unit did) however it was about a third the weight and within a minute of use realized it was a toy. I returned it and purchased a different brand; while better than the Karcher I'd returned, it is a far cry from my K 395 M.

I'm not a heavy-duty power washer. I don't want a gas powered unit (I have enough problems starting my gas powered lawnmower). I don't want to spend a lot of money on another unit (under $200).

If I could fix this one, it seems it might be my best solution.


    Bookmark   May 23, 2010 at 11:31AM
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I have a Karcher 2400 HH wthat is not maintaining constant pressure after releasing gun trigger. I would remove the nozzle, press the trigger allowing water to flow, replace nozzle and it would again pressure spray. This would happen every time I would release the trigger on the spray gun. Some times - after removing the tip - it would work - but IF I stopped even for a moment - again, NO pressure.

Appears a lot of folks have the same problem as I - and IF it is as easy as just lubing *after cleaning* the valve - using the waterproof plumbers grease - then I'll be SO grateful.

I am going to give it a shot now - and will come back with results of the fix.

Regardless - I wish to thank everyone for documenting their problems and fixes and suggestions!

    Bookmark   May 23, 2010 at 1:58PM
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OK I went ahead and used the instructions and the diagrams to locate / remove / lubricate / and replace the valve. Took me about 25 minutes to accomplish it all --- it IMMEDIATELY worked without any hesitation!

I need to thank everyone again in this forum for their information that was shared.

The only advice I can offer:
DO use plumbers water resistant lubricant - it is much more resilient and will last longer. I would also suggest at least once a season - to remove and lube the O Rings since the process is so simple.
Order replacement O Rings - and change every 2 years * more frequently is pressure washer is used a lot.

Thanks ALL!

    Bookmark   May 24, 2010 at 9:22AM
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I have the same problem mentioned above but I don't see the resolution.

Started leaking from unloader valves so I took apart, cleaned and sprayed lithium grease.

Now I start it up and the first time RELEASE the trigger the engine bogs down and tons of water sprays out the bottom.

Works fine when Trigger is held.

Any suggestions? Just clean it better? lol.


    Bookmark   May 27, 2010 at 3:28PM
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Hello Everyone, this is a great forum. Maybe someone could help answer my question.I have a Karcher 395 Electric Pressure Washer. After I replaced the plastic water inlet, It works but has little or no pressure.By checking the pump inside, I noticed that it has a very small leak.
I patched that with some strong cement. Now there is no leak, but also there is no pressure.I mean, the pressure got worse. My question is this: Was that little leaking hole that I patched a sort of Breather outlet? And that is the reason for pressure getting worse? Any help will be
appreciated. - Jaymes-

    Bookmark   June 30, 2010 at 2:14AM
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Hi guys, I am having the same problem. I did remove the unloader (thanks to the great instructions here!) it didn't seem to have much build up on it at all. I greased it up really well with Vaseline and shot some white lithium grease down the hole. It has not improved at all. My question is this, could I possibly have greased it up to much? Is there something else that might cause this.
After reading this thread I really thought this was the answer.
Thanks, Ian

    Bookmark   June 30, 2010 at 8:17AM
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I was having the same problem. Followed the 2005 instructions (uses white lithium grease not Vaseline) at the beginning of this thread. It worked great and fixed an issue that has plagued this Kracher 2400 since 2008.

Thank you to the fine minds department above.

    Bookmark   July 2, 2010 at 10:22PM
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I took it apart again last night, inspected, cleaned and greased it again. I still had to throttle down in order for the high pressure to kick in using the flat tip. I changed the tip to the roto style and if I held the trigger for about 5 seconds the high pressure would kick in.
Could there be something else causing this?
Could the unloader valve need replaced? It didn't have any real residue on it either time I took it apart, the o-rings look. I'm at a bit of a loss. If anybody has any other ideas I would really appreciate hearing them

    Bookmark   July 7, 2010 at 9:00AM
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Thanks everyone for all the advice! This project took a while for me to suss out but I now have my Karcher 2400 from Costco working now - amazing! I initially wasn't going to do the repair 'cos I'm not mechanically minded but - hey, I did it. Yes, even me!

A few things I did wrong - when you first remove the 2 screws and white plastic top bit, underneath there is a spring and metal piece, Well this is NOT the spill valve, that's the next bit that you have to pull out with needle nose pliers, this would not pop out even with the engine running and all hoses attached (a friend got it out for me as it was very stuck).
We couldn't get it out at first and so opened the main unit by taking the 4 bolts off but you can't access it from there and the oil will spill out if you do this - not recommended. Just have to pull very hard.
When we put it all back together water was squirting out from the top white plastic bit (remember I'm not really into this stuff;) I started it up anyway and Yay it worked great and the leak stopped too.
Hopefully it will keep going.
On the side Costco gets full credit back form Karcher for returned units (even ones bought years ago). And will take them back, If you don't have the receipt they can look it up. An employee had one of these faulty units and told me his tales of woe and so knew Costco's policy. (i couldn't take mine back as a friend bought it for me).
Thanks again everyone!

    Bookmark   July 17, 2010 at 10:12PM
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Thank you for the complete instructions. I was able to repair my K2400 Karcher with Honda motor easily. The unloader vas dry, and with a wipe of the rag to be sure there were no deposits, and a lubing for the piston, it works perfectly. As a tip to folks who visit here in the future, use the plumbers grease. I picked up a small container for less than $3.00, which should last forever.

    Bookmark   July 23, 2010 at 9:18PM
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First of all thank you to everyone who has contributed to this forum. I had the same problem with my Karcher K2400HH pressure washer and wish I had found this site before I tried fixing my unit. What probably would have taken less than half an hour became a six hour ordeal. All part number references are from http://www.pressureparts.com/k2400HH.aspx

Things I did wrong:
- I didnt know that the unloader (Page 3 #12 spill valve) existed and assumed I had to take the cylinder head (Page 3 #15) off in order to get to the pumpÂs components. I also didnÂt expect a bunch of oil to come gushing out when I pulled off #15 (which was also connected to the piston guidance Page 3 #4). One poster had asked about the color of the oil. Mine was grayish (probably due to metal mixing with the oil) with a hint of light brown. I figure my unit had run for about 100 hours before the failure.
- When I put the cylinder head and piston guidance back on I put the pressure washer on its back (pull cord was on the floor) so that I could put oil back into the pump (Karcher says to use 100 ml (3.38 ounces) of 15W40; a small engine repair shop recommended 30 weight non-detergent pump oil). That was a major mistake. Engine oil from the GC160 Honda engine ended up in the air filter, carb, and muffler. Needless to say it took some time to clean these out. I should have removed the pump from the engine housing at the four bolts (Page 4 #9), filled the pump with oil, and then bolted it back onto the engine.

A few things I found:
- If you have already taken the pump apart (piston guidance separated from cylinder head) you can access the unloader if you remove the joining piece (Page 1 #12). My unloader was stuck, and I was able to use a very small flathead screwdriver and push its spring up to force the unloader out of its hole (after removing all the components listed as #9 on Page 3).
- Someone had asked about where to find o-rings. I did a search on Ebay and there are places where you can get o-ring kits (30 different sizes, about 400 total o-rings) for around $20. I donÂt know what quality they are or if they are the correct sizes but if I have to replace the pump, hose, and wand o-rings IÂd be tempted to try these out. Worst case youÂd have an o-ring kit for your homeÂs faucets if none of them worked for the pressure washer.

One last note:
- When I lubed up the unloader the first time the washer would pulsate between high and low pressure (about three seconds high and then three seconds low). I removed the unloader and not only put additional white lithium grease on the o-rings but also tightened the unloader (while compressing its spring) clockwise by about one turn. It seems that the washer now eases slowly into high pressure mode where before I recall it had a harsher recoil after pressing the trigger.

Again thanks everyone on this forum for helping me get my washer back up and running. I hope somebody is able to benefit from the mistakes I made.

    Bookmark   July 25, 2010 at 1:32AM
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I have a K395m plus pressur washer and replacing broken plastic Karcher Water Inlet Elbow. took off top piece but can't figure out how to take the water inlet elbow off. Is there any link that shows how to do this without breaking something else?

    Bookmark   August 4, 2010 at 10:53PM
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So I have now found out that Karcher has the was tech support of any company I've had to deal with. My problem is I have a G 3000 BH that will hold high pressure for about 5 seconds and then go to low for about 2 seconds. (keeps doing this over and over) I have cleaned and greased the unloader valve but it didn't seem to work. Karchers part list shows the spring and then what looks like a o ring or something and then the unloader valve. (spill valve) Does anybody know what that is? Any more thoughts?

I'll also started taking the front off of the pump and some oil came out. (not all) What is the best way to put the oil back in? Above it said if I tip it back oil in the motor will get into the air filter, carb, and muffler. Any thoughts?

    Bookmark   August 5, 2010 at 1:17PM
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If memory serves me correctly there is an o-ring, copper thingee, and spring that sits on top of the unloader (spill valve).

This is my guess for the purpose of the copper thingee:
As the water is looping through the pump (engine turned on but trigger on wand not being pressed) it warms up and could potentially get too hot and damage the pump. I think the copper thingee will expand, thus not allowing it to be pushed against the o-ring. This should allow the hot water to be expelled through the white plastic piece (the first thing to come off after you removed the two torx screws).

If you have to remove the pump from the engine I think you will need to do it closest to the engine block. That is where I plan to remove it next time. I dont believe that any oil will leak if removed from that location. Once you have the complete pump separated from the engine block, then you should be able to remove the four hex bolts closest to the water inlet and refill your pump with oil. I found putting the pump back together is a lot easier if you have an assistant.

As for the pressure washer cycling from low pressure to high pressure there are two things I have read which might cause this:
- The flow rate of your garden hose may not be high enough. You might also check the pumps water inlet filter and make sure it is not clogged. You might also try removing any backflow preventers on your garden hose if they are present.
- If one of the valves on the high pressure side of the pump is stuck open (I think those valves are underneath the rectangular metal plate [1 inch by 3 inches] it might also cause this.

If you get your washer back up and running Id like to hear what you did to fix it.

Good Luck,

    Bookmark   August 5, 2010 at 7:14PM
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Hey Steve just got done working on it. When you take the 2 screws out all that comes off is the white piece, (that the screws go through) then up inside of that is a o ring, then a bullet looking brass piece, and then a spring. After that is all removed then is the unloader/spill valve. You said you think there should be a copper like o ring in between the spring and unloader/spill valve correct? It looks like there should be something there according to Karchers parts picture but they told me they weren't sure.
How hard is it to remove those other pressure valves? Is there oil or anything behind them?
How I got the oil back into the pump is by draining the motor oil so I could tip the pressure washer back somewhat and not have oil getting into the carb and air filter. Need a oil change anyways so that part worked great.
Thanks for the info and anymore would be great. This forum has been a great one for info.
One last question, could it be something to do with the wand and pressure hose?

    Bookmark   August 5, 2010 at 11:54PM
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I took a look at the parts diagram, and if memory serves me correctly there are two rubber o-rings on the white piece (the one that the screws go through). One is fairly small diameter and is buried up inside the white piece (this one makes contact with that copper / brass bullet shaped piece). I think the other o-ring is also connected to the white piece (where the white piece mates to the pump). For sure I didn't have any copper o-rings in mine.

I'm glad that you were able to get the pump filled back up with oil without having the remove the pump from the engine block. I'll have to remember next time to drain my engine block before tipping the pressure washer back.

I did try to remove that metal rectangular plate (with hammer and chisel) and got it to slide about 1/2 inch before I decided to try something else first. There should not be any oil in that section of the pump. My biggest concern about removing the metal rectangular plate was that if it had to come completely off those L-shaped hooks that it might be really hard to get it back on. I was also concerned that the spring loaded high pressure valves would come shooting out from those three holes once the metal rectangular plate was removed. Looking at the diagram there appears to be a plug holding the high pressure valves in place after the metal rectangular plate is removed . . . but don't take my word for it since I'm just looking at the picture. It is possible that crud / mineral deposits is causing one of those valves to stick in the open position. If you end up working on this section I'm curious what you find.

When you cleaned the unloader did you also use a tooth brush / wire brush to clean out the hole that the unloader came out of? And what was the condition of the rubber o-ring on the unloader (scuffed up versus new looking)?

I remember reading that it is possible for the nozzle tips to wear out (can't remember what the symptom is though). Have you tried different nozzle tips? And have you checked the o-rings on the pressure hose and wand?

Also do you get the same high / low pressure cycling if you run the engine at 1/2 to 2/3 throttle? If you don't you might try a web search for this and see if you can find anything. I can't remember what the possible causes of this behavior are.

Good Luck,

    Bookmark   August 6, 2010 at 2:31PM
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Hey Steve I tried a new wand and nozzle and it worked great. I then put my old wand and nozzles back on and it started happening again. Looks like after all that work it was the simple stuff. At least everything has new oil and is cleaned and greased. Thanks for your help.

    Bookmark   August 6, 2010 at 11:50PM
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I have a Karcher 396M. Upon turning switch to on, motor surges on and off continually, but when trigger is depressed motor will run full time while dispensing water under pressure. Let off the trigger and motor returns to surge mode. Why the surge and how do I fix it?

    Bookmark   August 14, 2010 at 6:47PM
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I have a lightly used K2400hh,several years old, which has lost hi pressure. Perviously this was fixed with a new unloader valve. Not this time, also tried all the suggestions listed above, to no avail. Pump bearing don't make any noise & Honda engine runs fine. Any additional suggestions on what may be the problem?

    Bookmark   August 21, 2010 at 5:35PM
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I've always found karcher washers to be good quality, mines lasted years. I don't use it every day but it does take some abuse! Tool Guru have a good selection...

    Bookmark   September 13, 2010 at 6:18AM
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I have a 2400 Karcher. Did the the cleaning of the uploader valve. I have pressure but the holes in the plastic cover of the uploader valve are spraying water. What can I do to fix this? Any help would be appreciated. Thanks

    Bookmark   October 7, 2010 at 11:36PM
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Is the o-ring in the plastic unloader cover in decent shape?

    Bookmark   October 12, 2010 at 1:59AM
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Yes it is.

    Bookmark   October 16, 2010 at 12:03AM
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My Karcher Model HD 2700 shuts down after 15 min operation. After 5 or 10 min I can start it up again but the cycle gets repeated. It has the Honda GX 200 engine.
I assume the engine quits due to 'overheating'.
The oil level is NOT low so I don't know what else might cause this interrupt operation.
I am a 'do-it-yourself' kind of guy and have no problem trying to correct the problem myself...if I knew the reason for 'overheating'.

    Bookmark   October 16, 2010 at 1:44PM
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Is the pressure nozzel bloced. This can prevent pressure from forming

    Bookmark   December 4, 2010 at 6:56PM
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    Bookmark   December 8, 2010 at 5:33PM
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    Bookmark   December 8, 2010 at 6:01PM
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Add one more success for the "tommyw" tip. After thinking I had a crack in one of the washers and changing them all out this tip fixed the problem perfectly.

Thank you for taking the time to post the tip!!!


    Bookmark   December 15, 2010 at 10:11AM
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Anyone have an answer to Mike's question posted by esoxlucius (My Page) on Sat, May 8, 10 at 12:48 on the high pressure hose connector leak? My hose connector, although tight, also flops loosely and leaks which affects pressure. Is there a seal replacement fix?

    Bookmark   December 16, 2010 at 2:57AM
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I have a Karcher pressure washer and found helpful / interesting reading all the forum notes. My problem - where is the uploader value on the KArcher model 3025? I am ready to attempt the repair of the value as suggested by so many folks, but I don't see the black removeable piece on my machine. Someone please tell me where to get started on the project by locating the value. Thanks.

    Bookmark   December 25, 2010 at 8:45PM
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For anyone interested here is a link for the Service Handbook for the 3.532-629.0 washer pump used on the K2400HH model.

    Bookmark   February 1, 2011 at 7:41PM
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I have a K2.26 M and i cannot get any pressure out of it..I just have it for almost a mont..i tried the mixing option once with some bleach - detergent...
it started leaking two days ago heavy and loosing pressure...today he had no pressure at all...
can anyone help me? Thank you ,Gilbert..

    Bookmark   March 28, 2011 at 9:03PM
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Help Please! Have a used Karcher 395 electric pressure washer. Prior owner said he only used it twice. It does look new. Tried it and have no pressure, just light stream of water which shoots about 6 feet. There doesn't appear to be anywhere on the machine or the wands to regulate pressure. Am I just doing something wrong. Also why does it have two trigger guns. Thanks for any suggestions.

    Bookmark   April 1, 2011 at 2:04PM
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On my 2500 VH, I too pulled the pump and am in need of servicing it after reinstallation. I have read two threads, one stating to unbolt the pump from the motor and add oil that way. The other is to drain all the oil out of the motor and turn the unit upside down and service the pump. Which is best or is there another way? It seems to me that even if the motor oil is drained, a small amount will very likely still leak into places it shouldn't. Any advice?

    Bookmark   April 6, 2011 at 12:32AM
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all you guys who had water spraying out top of unloader cap and some pressure and motor bogging down when let go of trigger, same thing happened to me :)

i put back together in correct order and all works great.

unloader valve goes in housing, then spring goes on top of unloader valve, then brass valve thingy then cap.


    Bookmark   April 9, 2011 at 4:23PM
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The basic $98.00 unit with no wheels don't know mod no.
When 1st used new out of box, it took several minutes for the pump to kick in. I thought it was maybe usual for a new unit to prime pump ?? or similar.
But after a few months in the Garage it won't start at all.
I only get tap water preshure thru the unit.
Lost reciept. Hardware shop just say sorry. Might have to try a Gerni unless someone can advise me.

    Bookmark   April 24, 2011 at 11:46PM
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I have a model K3.86M 1.636-121 Karcher pressure washer, Serial Number S 341586 1/05 that has a water leak and I took out all the screws but cannot and don't know how to take off the blank part that has the handle on to remove it to see where my water leak is. What is the trick to remove that handle part?

    Bookmark   April 25, 2011 at 4:28PM
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I have a 2-3 yearold pressure washer that has been used only once. The problem that I have is that there is nno pressure. Please explain what it could be. thanks

    Bookmark   May 5, 2011 at 11:43AM
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i have replaced the fuel hoses to my washer hds501c now it does not seem to be getting fuel do i have to bleed the system as burner will not start

    Bookmark   May 7, 2011 at 3:27PM
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I have a karcher mod# K3.47M. I always put the washer in the garage after use. We had some very cold temps this past winter and the discharge elbow cracked. I went on line and bought a new elbow #9.036.7030 and it would not fit. The serial # is 027270. Can anyone tell me what # elbow i need and where to get it. Help,Bill

    Bookmark   May 7, 2011 at 6:07PM
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I did the grease thing (had to start the washer, with water on -- a geyser poped out the piston). Still did not work ... I adjusted the engine RPM down (phillips head screwdriver to adjust the RPM) & now it works great. I'm sure the grease was the issue, I monkeyed around with the carb yesterday & just left it at high RPM. Clearly a pressure-feedback piston .. engr should have made it out of teflon ...

    Bookmark   May 8, 2011 at 1:59PM
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Wish I saw this before I attempted to repair my 2400.
Finally found the spill valve nothing was gettin it out pliers worked it back and forth pb blaster, brake clean etc. FInally took out the 4 bolts so I could get needle nose vise grips on it. Worked back and forth for 20 minutes. Finally poped out. Cleaned valve and housing with 3 m pad greased and reassembed twice Now I have to idle to get pressure and hold trigger and increase RPM to maintain pressure. Hlep! should I grease it again?

    Bookmark   May 11, 2011 at 7:22PM
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Re: K 2.360 - Piece of junk . Brand new . Bought from Wallmart Today . Motor will not start . I have 65lbs of static water pressure . 120volts AC . Tested the GFCI and it passed . Pressed reset again . Switch is in the ON position . Trigger is pulled . NO MOTOR FUNCTION . Can anyone help , or do I take it back ?

    Bookmark   May 22, 2011 at 12:34AM
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I have white oil below pump housing. what type oil do you replace with and is it supposed to be at the clear window level on the side of pump. I have Karcher HD 3101

    Bookmark   May 30, 2011 at 4:18PM
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I have an Karcher 395 pressure washer that doen't turn off when I release the trigger. After reading, I can assume it has something to deal with the spill valve or pressure control valve (see http://www.fixya.com/support/t5329991-motor_not_shut_off_when_trigger_wand).
Can someone assist me on exactly how to service it?
I already removed the cover including the electrical box which I figured the switch that has 4 leads to it is the switch that shuts off motor as pressure builds when triiger is not engaged, as there is a plastic piece that ends outside of box trough a rubber gromet that should react act this occurs. Assuming I understand the design, I figured the valve is the part with 1 screw attaching it, which has a metal rod.
Is this what I unscrew and if it doesn't come out by itself )which it does not), turn motor on/off quickly to make it pop out?
Please advise if I am correct along any additional info you think will be useful.
Thanks in advance.

    Bookmark   June 25, 2011 at 1:06PM
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hi there, to all you frustrated pressure washer users, its self evident that this is a demic product with all the problems attached to them, I'm going back to the good old reliable bucket and water, lifes too short.

    Bookmark   June 26, 2011 at 5:59AM
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I have used my Karcher pressure washer very little, however, I have a problem, after it runs for about 15 minutes it shuts down. I have stopped it and as soon as I use the spray handle, it stalls and goes out.. I got about 1/3 of my deck done, so now I am borrowing the electric pressure was I gave to my daughter. Any suggestions?

    Bookmark   June 27, 2011 at 9:51PM
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I have K390 karcher pressure washer when I try to turn the machine on machine on it will not start it was working but but that was only accasionaly before is there a electronic switch behind tha botton if so where can I get one and what is the part number
thanks Jack

    Bookmark   June 29, 2011 at 11:36AM
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I've got a 6-year-old Karcher 2400 which I just brought back from the dead following the instructions on this site. I'll sum up, and add a photo:

1. Rebuild the unloader valve following the instructions on this site. See photo for location of valve.
2. Be sure to attach the sprayer hose and turn water on full blast before starting up motor--I couldn't dislodge the piston until I did this, and the fix didn't work until I did.

Upon performing these steps to the letter, I brought back an old Karcher that I thought would never work correctly again. Good luck.

    Bookmark   July 23, 2011 at 10:57PM
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I have followed all of the advice regarding low water pressure on a Karcher 2400HH machine. I have replaced the "spill valve' with a new one and lubricated it with Silicone plumbers lubricant. The pressure is much better but it occasionally dies and then resumes at full pressure. Is there something that I missed or is an additional step necessary?

    Bookmark   July 27, 2011 at 6:20PM
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I have a K3.99 pressure washer. I use it about 4 times a year, and I think it is only about 3 years old. I had used it the week before and everything was fine. I went to turn it on this past weekend, and the power is completely dead. Is there a fuse inside that I need to replace?

    Bookmark   August 10, 2011 at 10:53PM
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I registered for this forum simply to say THANK YOU to those who offered advice about the unloader valve on the 2400HH. It had never worked properly from the day I bought it (new) several years ago, but I [wrongly] attributed it to bad water pressure from the tap and was just pleased when on occasion it would "spring to life" and provide real pressure (perhaps one time out of ten). The problem continued even after moving to a new house, by which time I was well out of any warranty and I just resigned myself to living with it, figuring I had gotten a lemon and was stuck with its quirks (unless I wanted to pay a repair shop a ton of money to sort it out).

I stumbled across this thread looking for something else today and immediately went out to follow the advice offered here. Wish I had done this years ago -- it works MUCH better now than the day I took it out of the box! Thank you so much! Can't wait to see my water bill for the month, as I've been going around for the past several hours looking for anything that looked like it could use a good power washing. :-)

    Bookmark   September 4, 2011 at 5:05PM
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I have a Karcher 330 (electric) used very little - problem is.. no pressure.. any suggestions..

    Bookmark   September 21, 2011 at 5:00PM
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Hi all, am new here after Googling problems on Karcher 2400 HH purchased at Costco about 5 years ago. Having the same pressure problems as many. I have broken the attachment fitting off the end of my trigger gun and am awaiting the arrival of a new one that I ordered from PressureParts.com. They informed me of this unloader problem. So I get to it and can't get it out either. Couldn't get any tool in with that cross member in the way. Naturally I hadn't got here yet before loosening the pump front and spilling oil. Doh!So pulled the whole thing off from engine and struggled but got the spill valve out with needle nose vice grips. Not really caked up at all but O rings were brittle and beat up looking. So I'll get some new o rings and get it it greased up while waiting for the new trigger gun. As well as getting some of this unobtainium oil and either topping up or replacing. Like others have mentioned it doesn't look as good as one would hope it might. Apparently a lot of these guns broke like mine (where the tube is soldered to the threaded fitting) and they have redesigned the plastic housing to better support that joint. Hope to have some good news in a week or so and share any thoughts and experience as many of you have done. Thanks to all!

    Bookmark   September 27, 2011 at 8:27PM
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Oh and wanted to mention a couple of things:
1)Most hardware and auto parts stores have vast collections of o rings you can buy individually. Take in your old ones to compare and/or have them measure with a caliper or micrometer.If no luck there try McMaster-Carr online. They are wonderful for all kinds of things.
2)If you live where it freezes like I do in CO and if you have or can borrow an air compressor and an air nozzle you can blow the water out of your pump and hoses. I have done this successfully for at least 6 years that I've owned it and I store it in a shed that gets well below zero at times.
Hope this is helpful!

    Bookmark   September 27, 2011 at 8:45PM
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I lubed my Karcher's unloader with plumber's grease last year and it worked for a while. Took it apart and found the sides of the piston and cylinder were free of grease and dry. Going to use lithium grease as suggested.
About winterizing. I buy RV antifreeze that WON'T HARM THE ENVIRONMENT! Suck it out of the bottle with a piece of hose attached to your inlet and spray it out of the wand until everything is flushed and filled with the antifreeze. Just hook up everything normally next season and spray it out on the ground, over the lawn, whatever. It won't hurt anything and once you're spraying clear water get to work.

    Bookmark   June 21, 2013 at 9:30PM
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Have been having unloader problems for years on my karcher 4000 PW. Finally learned the water pressure trick to eject the unloader and now keep it liberally greased. Last time i reassembled the valve I wound up with low water pressure and started disassembling, then cleaning the entire pump head with no improvement. Obtained an exploded view diagram of the pump and found I had the brass bushing atop the unloader backwards. Flipped it around and had great high pressure!

    Bookmark   September 21, 2013 at 2:26PM
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