On Nov 11, 4:46 am, shinydoc
wrote:
Thanks. I have done that and use fresh fuel every time.

Very occasionally it works first time without any problems, which is
why I am confused!

--
shinydoc

If you know a shop (technician) whom is very knowledgable I would
suggest you ask about getting the next "hotter" sparkplug that fits.
(He should be able to give you a spec-list.) I have done this for all
kinds of internal combustion engines with all kinds of starting
problems, and 100% of the time it has helped. On rare occasions (1 or
2 cylinders of an automobile engine getting oil-fouled repeatedly) I
have used a plug 2 grades hotter. It works. The plug may burn-out a
little sooner, but that's a trivial inconvenience compared to a
nonfunctional engine.

Don