Be sure you have the water and solution in the correct tank first. Then push up on the small valve on the bottom of the clean tank. If it does, the machine may need to be primed. Put the tank back into the machine and ensure there are no gaps between the tank and machine. Then clean out the spray tip with a paperclip or old toothbrush. Also, check for spray without the tool. If it is not suctioning, make sure the dirt tank is not full. Feel for suction at the motor duct on the machine. If there is suction, check the duck bill gasket and ensure it is not stuck together and that it is replaced correctly back in the tank bottom. Make sure the float stack is in the dirty tank correctly as well.