Shutting down engine Question

Lisa wrote in message ...
Perhaps this doesn't matter much for a non-turbocharged engine,
but an instructor says that it is best to idle the engine at
1,000 RPM for a few moments before Mixtu Idle Cut-Off at that
RPM to shut down.

The POH says throttle full aft, then mixture cut-off to shut
down.

Which is best?

The idle at 1,000 RPM sure helps in my IO-360 engine. My engine hot
starts great, and cold starts great, but is very hard to warm start.
Idling at 1,000 RPM (or 1,200 RPM) for a couple minutes seems to make
a huge difference.

-Robert

When we used to run Cessna 150s, we often found them hard to start.
Then we noticed that just after a flight, or lengthy runup before
inspection, that oil would dribble out of the bottom plug holes when
we pulled the plugs. These engines tend to foul the bottom plugs at
idle for some reason, and we instituted a 1700 RPM runup prior to
shutdown to clear them. No more hard starts or fouled plugs.
We have few fouling problems with the Lycs, other than with too
much circuit work.

Dan