Sla#s wrote:
As mentioned above, when you have finished with it drain out the fuel, then
re-start it and run it until it's dry.
If you are leaveing it over winter, change the oil if four stroke, clean the
filter and whilst you have that off spray a little WD40 in the carb whilst
pulling it over.

WD40 is horrible stuff to do this sort of thing with, it leaves a
sticky deposit which all sorts of dirt etc. sticks to. It's not a
lubricant, it's a water dispeller. Used on ignition systems in my
experience it works to get a wet engine started but if used too often
so much filth ends up stuck to the ignition leads that they need
replacing after a while.

I'd go for plain engine oil or similar if you really want to put
something "in the carb", but I don't think it's necessary.

--
Chris Green