Thanks Big Ted
All of you provide a wonderful service, a mine of info & I am grateful to have found it.
It's been a right bggr having problems over Xmas/New Year.
Yes, the greasing is a temp measure only. The oring will be replaced.
The cut out boot is just under a year old, the previous one had perished & split. When I went to reset the probes I eventually found that the grommet had popped out from the carb body so I'm pretty sure that was a major factor. Once I re-seated it, all good!

Cheers
Pat