check the main feed pipe to the washers you may find that there is a kink in the pipe near to the bonnet hinge which closes the pipe when the bonnet is close but is open enough with the bonnet up. if this is the case a small piece of plastic tubing maybe required or simply re-route the pipe, you could try to re-enforce the pipe by supporting it with a piece of plastic on the outside to prevent it bending. MRW
Mark, November 2010