Originally Posted by
Weeds round the prop
I still find it hard to believe that a spark plug can be changed on a running engine, having witnessed the result of one unscrewing to the end of its thread and zipping off over a hedge, never to be found again-
A largish radial will continue running even if one cylinder isn't cooperating. So if you pull off the lead(s) for one pot at a time, you should be able to change the plug(s) that way. The difficult part is probably getting the new plug in without dropping it
Not saying I'd like to take on the job though....