Question about Karcher G3025OH Pressure Washer

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How do I fix a pressure washer that will not build up pressure quickly and when it does reach high pressure, the pressure quickly drops to a lower pressure (more typical of the pressure found in a garden hose)

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  • gtownsend Sep 04, 2010

    I had checked the hose on the inlet side of the pump. Someone had removed the screen, and I don't know if there has been stuff in the water running into the pump and has done any damage or not. this washer's water is supplied from a poly tank via a Honda pump which pressurizes the 3/4 inch hose to the pressure washer. Water sitting in the tank grows algae, etc. is it possible that there is stuff stuck in the pump that can be cleaned out somehow?

  • gtownsend Sep 06, 2010

    i will try the vinegar solution. thanks



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It can be the inlet filter where your garden hose connects is clogged, so check that first. Also make sure that the hose is connected tightly and not pulling in air both at the inlet and outlet. Remove the spay nozzle and use a pin to make sure it is clear on and debris. Pull the trigger wait until you see a constant flow of water, and all air has been purged from the system. Then attach the high pressure nozzle. Black nozzle is for low pressure. Also make sure you are using at least a 5/8" garden hose and no smaller with the water turned on fully. Check the hose for kinks and obstructions. If all this checks out you may have calcification. Use the black low pressure nozzle and a gallon of distilled vinegar and inject it through the unit to remove any calcification. If none of this solves your problem then there is a problem with the pump itself and you will need to call Karcher for repair or replacement of the pump. Although your unit has a thermal relief valve, you should not run this unit for more than 5 minutes without pulling the pressure washer trigger or it will overheat and damage the pump. If you find you need a new pump here is one for $142.

Posted on Sep 04, 2010

  • NOT ME Sep 04, 2010

    It is possible, but the vinegar should clean it out. The pump may have been damaged due to the inlet screen being removed and some debris entering the pump.



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