my karcher k 3.68 jet washer is pulsing when switched on but trigger not engaged

percy, January 2010

Is there a place to find a replacement on/off dial switch on Karcher K3.68 M power washer. That appears to be the problem - will not turn on at all and have checked all electrical outlets. Thanks for any help.

judy, July 2014

Recently my Karcher K3.68 also began its leak while under motor pressure. I know it was not freezing temperatures and am curious about one thing. It is coming from the same part number 97760580 which Karcher confirmed has been replaced by part number 97551120. Same part - just a new "tag" number. The part that has me curios is this - owned if for two years... and I have gotten my monies worth out of her in some lengthy projects. I have NEVER taken the gun hose off.... until the night before it began its leak. I used it all afternoon and once again had my fill of the stupid hand cramping non-user friendly cheap plastic gun handle and trigger. I took the hose off because I decided to upgrade to a better quality hose and user friendly gun and attachment nozzle. Took the old hose to Lowes to match up an upgrade - came home and upon flipping the switch = new leak. Thinking the new hose isn't working - re-installed the old hose - still new leak.... realized it was internal and not the hose connection and here we are. Here is the curios part --- is there a chance that the twisting (unscrewing) of the old hose caused the stress crack? Is it possible others with this issue knocked over the pump in use or bounced the hose connection on something in storage? Is it just a fragile joint? Let us ponder.... hmmmm????

Karcher UsedaUser - Now upgrading?, March 2012

you have air in the line - shut it off..... leave the hose on only and squeeze the trigger and let it run with only hose pressure to get the air out of the system (I usually do about 45 - 90 seconds depending on variables like empty hose full of air or hose lengths of 100ft plus) I let it run with NO nozzle in the gun and it usually spits and sputters the air out within 30 seconds - double the run time to ensure no more big air burps. Let go of the handle - attach you nozzle - turn her on and she should pressurize and shut off - no more pulsing.

Karcher User, March 2012

Same problem with mine. It has NEVER seen freezing temperatures.

G. Lockwood, March 2012

I have the same problem with this model, but it has never seen freezing temperatures. There is a water passage near the top of the pressure control piston, and the housing cracked from that point to the outside. Hard to see when there's no pressure, but when it's on it leaks like crazy.

97760580 seems to be the old part number, one place claims the replacement is 97551120. Trying to find the best price now.

Wheels17, September 2011

sounds like you have the same issue as mine - just stripped it down and am also getting water leaking from Cylinder head area every time it pulses. I didn't empty it out enough and think frost has created a crack in the head housing. think spare part is 97760580 am just off to check. Then got the enjoyable task of rebuilding it.

Dan Mudd, March 2010