Question about Karcher 2500 PSI Pressure Washer

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+pump will not develope full pressure - Karcher 2500 PSI Pressure Washer

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The most common cause of this problem is one or more of the valves in the water pump it stuck or damaged You should see 6 caps on the pump body the valves are under them . Take the caps off one at a time pull the valve out and see if it moves it has a cage and a spring under the valve seal if it moves and seats ok then its good The bigest problem is the machines get stored out side in the winter and if the water pump isn't drained and filled with antifreeze the water in the pump when it freezes expandes and it can crack the plastic on the cages and the peice will stick in the valve seal. But most of the time if you just remove the peice the valve will be fine. The other thing that could be wrong is called the unloader valve witch is the part that has the knob on it to adjust the pressure. What it dose it is open when the trigger is released to allow the pressuere to recirulate inside the pump .If this valve is stuck open you would not be able to build pressure . Unfrotinatly most are not serivceable and need to be replaced as a unit . Every body sells a powerwasher but most of them are made with parts from 8 differant companys its all jobed out and they stick there name on it . So sometimes its tricky to find the correct company to get the corrcet part from . Try the body valves a lot of time it will be the problem and even if you need to replace them there are common to many differant machines and not that hard to get Good luck with it

Posted on Mar 20, 2011

  • JOHN LAPIER Mar 21, 2011

    I didn't relize you were the same guy who rejected my answer before .So do what you want but im rebuilding one right now its on my desk just got through the engine issues and now im adjusting the unloader and undoing want the last guy did wrong to create the problems on this machine and its twice as big as the home owener unit you owen Lots of luck i'll remember this time


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