Thanks for all the advice chaps, i eventually managed to get the old girl running. I siphoned as much petrol as i could from the tank, i then removed the fuel filter & soaked up the petrol in the chamber with a clean lint free cloth. I filled the chamber with fresh diesel & replaced with a new filter. Filled the tank with £90......"kin £90" of diesel,(its been an expensive learning experiance what with the £40 of contaminated petrol i've had to dispose of) I hope i NEVER do again.... I then cranked it over.... lots of smoke & spluttering untill she fired. I took it for a blast down the local bypass, bit of smoke at first but it cleared & now it runs sweet, if anything,, better the before. Starts ok too. Once again, thanks for all your advice.