Hi,
It sound like the spill valve is stuck, this gets stuck when the pressure has not been released from the gun the last time the washer was used. Remove the motor from its casing then Remove the 4 bolts in the top of the assembley. Take the top off the black housing assy and the spill valve is inside that housing, It can be removed, cleaned & refitted. The spill valve is in this part as shown on http://www.candmdomesticappliances.co.uk/product.php/1929/483/control-head-for-karcher-jet-pressure-washers) below the white cap is where is spill valve is situated. hope you understand all of that.
www.candmdomesticappliances.co.uk
paul
April 2009
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