The following article is taken from the AMA National Newsletter.
Please see bottom of page for contact information.
This article is by Bob Angel from SAM 26.

PIT FIRES

Over the years, we've seen a lot of flame ups during engine starting. Most were as easily blown out as a set of birthday candles. I recall two occasions where some damage was incurred. In both cases it was with cowled engines, where blowing just seemed to supply more oxygen.

The first fire occurred with a backfire after a prime during engine starting. The other case was my own 1/2A Klemm, right after installing an older open exhaust port Babe Bee engine. I'd replaced a slit-port modern Cox that needed some tune-up. That's when I verified that Cox introduced those double slitted exhausts to snuff flame fronts from escaping the engine and causing fires. The open port engine caught fire the very first time I tried to start it inside the cowl. Fortunately there was minimum damage that time.

A simple plastic water spray bottle is usually all that's needed to snuff most fires, especially for alcohol fuels. Water dilutes and cools the alcohol. The CART and Indy car race teams burn alcohol, and water is their fire extinguisher of choice for fuel fires. Most conventional extinguishers must be replaced after just one shot, and their chemicals cause damage.

from SAM 26
Bob Angel, editor
1001 Patterson Rd
Santa Maria CA 93455