Pressure Washer

[Geoff]

Anybody know anything about pressure washer faults and repairs?
I have had a Karcher 620M for quite a few years but today it has given up on me. Used it Monday quite happily but today it won't develop any pressure. It has not been frosted in the meantime. Checked the inlet filter. Water runs through and the motor runs but develops no pressure. Any clues as to anything I can do myself would be much appreciated. Has anybody ever had one repaired and is it likely to be economical or am I looking at a new one? I have emailed Karcher Customer Service for advice but no reply as yet.

[arthur e]

Hi Geoff, One day I heard my Karcher running in the shed, what had happened was It had switched itself off at the end of a wash and I forgot to switch it off physically. This meant as the trapped pressure bled off it started up and ran dry and it melted the 3 piston seals in the pump. I shopped around on the web and found the bits and changed them all myself, fairly easy job to do if you have a bit of mechanical skill.
Arthur

[oldherbaceous]

Dear Geoff, i know this is a bit of a long shot, but just check there is not a little bit of grit just behind the tiny hole in the nozzle on the gun.

[Geoff]

Thanks for those. I haven't worked out how to remove the body to get at the workings yet - a job for after dark. I have the feeling it may be a sticking valve or something like. I don't think it is blockage on the output side as water runs through and I tried it without the nozzle. Karcher don't seem to be offering a self help route so I guess I'll have to be true to my signature!

[Larkshall]

I have an old Karcher washer which does not always come on full pressure, I just jerk the trigger on and off several times. It is a bit erratic.

[Geoff]

Well I took it all to pieces shortly after the last post and decided I didn't really understand how it worked but couldn't see anything obviously wrong. Decided to leave it in bits until an engineer friend passed by to get a second opinion. When he didn't turn up, as he has his bathroom in bits and is under curfew until it is finished, I cleaned off odd bits of dirt and scale and put it back together. It worked and I washed the car with it but there was a slight leak. Took it apart again and identified a couple of polygonal o-rings that were probably the culprits so ordered and replaced them. Put it back together and was back at square one with it running but not pumping. Left it on one side while the weather was fair then this evening we had the first daylight rain for weeks so again took it apart, again couldn't see anything wrong, put it back together and it worked fine.

So it proves once again ....................