to answer my own question!
On removing the bottom tray I found the hose connecting the spray pump had come off, it was only held on with a plastic cable tie!
I have replaced this with a jubilee clip and now running test wash.
This is the second time this has received atttention, the first time under warranty, surely not very good design, as this joint is close to the main motor and must spray water on it when it leaks.
John, November 2011
