"Robert11" wrote in message
. ..
Hello:

How long, typically, is a spark plug good for in a typical lawn mower, and
also for a typical weed-wacker, before needing replacement ?

Assume, perhaps, once a week usage during the summer on each.

Thanks,
Bob

pull the plug and check its condition first of the season.
Here is a page that will show you what to look for.

http://www.verrill.com/moto/sellingg...colorchart.htm