After a bit of messing about I restarted it by aspirating the air intake with propane. I then ran the fuel return into a can and it was milky white. On pouring it through MR filter I ended up with 0.5 litre water from 30 litres of petrol. The vast bulk of the water in the first 5 litres.
I have yet to see how it got in but I suspect the pump under the wheel arch is sucking air and getting splashed in puddles.
AJH