Do you have a problem with your Karcher pressure washer losing pressure? There is a good chance that you have a sticky unloader valve inside of your pump. We know that it can be frustratingtrying to deal with this issue but really can be an easy fix. There could also be some other symptoms that can indicate a sticky unloader, these might be:
1. Complete loss of pressure
2. Pressure on machine is cycling on and off
3. Machine only has the pressure the garden hose puts out
4. You have to take the nozzle off the machine and run the machine in order for the high pressure to kick back in
Follow this link to fix the unloader problem
If you have a problem removing the unloader from the cylinder you are going to have to hook the machine up to a water supply and try to force the unloader out. Sometimes it might require that you fire the engine up to remove the unloader, if you have to do so make sure to have something to catch the unloader over top of the pump (rag, towel, bag, piece of wood). If the unloader continues to be stuck we recommend pouring vinegar into the cylinder and letting it sit for 3 or 4 hours with the garden hose and high pressure hose hooked up to the machine and then try the removal process again.
Tags: no pressure, pressure problem, revised unloader, sticky, unloader
I followed the instructions and the unloader, it only took me about 10 minutes, glad I found this article, I almost threw the pressure washer out.
When I took the valve out there was a great deal of white powder that was built up in the cylinder that the unloader moves up and down in. From what it looks like this might be hard water deposits, does anyone know if there is anything that I can do to prevent this build up from happening again?
We have seen this very often, usually this build up is caused by water sitting in the pump for long periods of time with out being used.
There are a couple things you should do to keep the build-up from happening again, these included:
1. Drain a majority of the water out of the pump, you can do this by pulling the engine over 3 or 4 times after your done using it, make sure the engine is turned off and the high pressure hose is disconnected.
2. We also recommend purchasing a inline filter to protect your pump from incoming sand and sediment from your water supply.
3. Another thing to consider is to use a winterization product on your pump in the winter. Karcher makes a product called “Pump Guard”, this product will also prevent any water from the inside of the pump from causing damage by freezing during the winter months.
i released the unloader and the pressure is just a bit better, is there anything else i can try ? thanks
If your pressure only increased a little bit then I would recommend replacing the unloader with the revised one. We have put many of the new revised unloader valves into machines that continue to have pressure issues and have had very good results on getting the pump back to full pressure. The link for the revised unloader is at the top of this page if you want to replace it.