Thanks for the advice all noted , I have contemplated fitting a modern or even a classic solenoid as you have described but I would really like to keep the originality of a pre war solenoid . I'm sure in the end I will be buying a modern but I have not reached that stage yet . Steve hall has been most helpful in suggesting a few ways to get my original working properly again but my current solenoid is sealed which makes any service impossible unless I open it up and risk ruining it completely . Any suggestions very welcome .