Sort of off the subject but along the same lines......
If a diesel engine gets "fuel" into it's airstream while running it is very hard to shut down and it will rev very high.
The only way is to shut off it's source of air.
Now this fuel can be alot of things, a turbo seal leaking oil into the airstream
(I know this engine isn't turbo'd) an over-oiled "reusable air filter" etc.
The point I'm making is that ANY diesel engine can have the same thing happen, a run off, but you hardly ever see it in an owners manual.
BTI