Unloader Valve - Karcher Pressure Washer

According to epowerwash.com:
"The unloader valve diverts water flow into bypass when the trigger gun valve is closed. Unloaders may be designed to respond to either an increase in pressure or a change in flow. The unloader valve may also be used for variable pressure adjustment."

More information here:
All About Unloader Valves ePowerWash

hi there rjcomer2

here is web site for parts
http://www.ereplacementparts.com/karcher-2500-11944010-pressure-washer-parts-c-33388_33389_33973.html

sounds like you have a unloader valve problem or a crack in the pressure manifold housing between pressure outlet and unloader valve assy allowing unloader to cycle on/ off

or some dirt trapped in the unloader valve seat , make sure you have good supply of water - ie good flow from tap to pump

try cleaning unloader 1st and fitting in line tap filter

hope it helps

pauly46

If you have pulsating usually you have at least one of the six check valves stuck open, so you're only running on two cylinders. You might have got some of your plumbers " grease" in the check valve. (Do you mean pipe dope?) three of the check valves shold be accessable from the outside of your pump but the other three are inside. You can get parts for your unit from www.pressure-washer-parts.com

Hi, Karcher calls the unloader valve a spill valve,
this is a link to a full drawing/parts listing , and your fault description might well be a sticking /seized unloader(spill ) valve hope this helps
http://www.pressureparts.com/ManualViewPage.aspx?Manual=/mmDEV/PDF/karcherparts/g2500vh.pdf

the part number is on page 9 of the drawing
spill valve 45910400
hope this helps , we usually use some good quality silicone grease to lube the valve ,

Hi:
Cleaning it is not enough. You need to make sure the o-rings are in good shape and grease it with a very very good waterproof grease. Here is a schematic of the pump. The unloader is parts 7 to 13 on D-2

Hi ruthkapres:
Here is a diagram. The unloader/spill valve is #12 on page D2 or F2 depending on your model. You must pull it out, inspect the o-rings for dents or tears and make sure the valve is lubricated with a good water proof lubricant.

The Karcher K2400HH and G2400HH do not have an unloader valve, they have a spill valve which is located under the black cap on top of the pump.

The spill valve needs to be removed and the side walls of the hole it sits in need to be wire brushed to remove deposits. then you can put it back in and put the pump back together.

http://www.landanorthwest.com/documents/instructional/spill_valve_instructions.pdf

The unloader valve usually is replaced. I dont know if you can get o-rings for it. But if you want to take it apart, there will be a crown or cap style nut just below the spring. Unscrew it completely and you will be able to remove the spool. There is just a series of o-rings on it.

I am waiting for the mfg to provide me details on how to clean the unloader valve at this time.