On 2007-05-15 16:28:54 -0700, EridanMan said:

Interesting topic, interesting discussion... but if I may expand on
the original question a bit?

The Original piper POH that came with my bird ('67 PA-28-140) actually
recommends that that prop be pulled through two complete rotations
backwards any time the engine is started after sitting for a long time
(it actually says its a good idea for every flight, but should be
mandatory any time the engine's been sitting for a while).

I've NEVER heard or seen this advice anywhere else... I've never
practiced it... It seems almost insane to me... but the book says
what the book says.

Anyone have any clue why?

I can get the exact wording tpmogjt ... its in the 'preflight and
takeoff' section of the book.

This is also recommended in at least Cessna 172 manuals for cold
weather starts. The idea is that oil that is cold or has been sitting
awhile is thicker and more sluggish. Pulling the prop through limbers
up the oil some, so the engine does not have to work as hard while
starting. It can make all the difference in whether you are able to
start the engine or not.
--
Waddling Eagle
World Famous Flight Instructor