obvious as it sounds!
http://consumerist.com/2011/01/dont-unclog-a-snowblower-with-your-hand.html
One Quote:
Additionally, there is a 50% chance that both valves on the engine
were closed when the engine stopped (depending on where it was in the
engine's cycle). This can, in turn, mean that there are compressed
gasses pressing against the piston. This, in turn, is good for up to a
half-turn of the crank shaft. This half-turn could go either
direction; which direction depending on whether the engine was in its
"compress" or "power" phase. It won't do this if it is in "intake" or
"exhaust" phase, as one valve will be open, relieving any pressure.
It gets more complex if the engine has more than one cylinder.
--
TSA is the DRM of travel. They inconvenience all non-terrorists (paying
customers) and seem ineffective at stopping terrorists (pirates). - @arwyn
