Run up for plug clearing

On Sat, 09 Oct 2004 07:30:28 -0800, Dale wrote in
::

In article ,
Larry Dighera wrote:


That's what I was taught. Often it only takes 10 - 15 seconds to
clear/burn the carbon deposit without the necessity of leaning. I
don't see anything abusive or abnormal about this procedure, as the
engine sees full throttle on each takeoff.

A difference between a runup and the takeoff roll is the cooling air
flowing thru the cowling when moving.

True.

There is very little airflow when stationary, even with high power settings.

Are you able to cite a credible source that supports that assertion?
I'm not saying it isn't true, but I'd like to hear the input of an
A&P.

I'm not saying you shouldn't do a high power runup, but you should be
cautious and aware of the possibity of heat problems.

A pilot should always be aware of that possibility.

As the plugs tend to foul more easily when the engine is cold, the
admonition for caution in this instance is mitigated by the fact that
the engine temperature usually hasn't reached a point where it is a
factor at run up time. At least here in California that is what I've
found. In colder climates plug fouling may occur more frequently, but
I would expect the ambient temperature to also mitigate the cautionary
advice.