engine starting in The Great Waldo Pepper

[Joe Broady]

Recently The Great Waldo Pepper was on the Turner Classic Movies channel. Interesting how they hand propped the engines: pull the prop backward a fraction of a revolution then release. The prop springs forward and the engine starts. That's shown three times in the first 20 minutes of the movie. I'm not sure how that works, or if it would work in reality. Maybe the principle is something like what I read in a book from the Ford Model T era. If you primed the engine just right, and carefully positioned one of the pistons at the right spot, the mixture would fire when you switched on the ignition and crank the engine like a motorcycle kick starter. That trick was called starting the engine "on the spark."

 

[MiTasol]

In the Waldo movie case it was pull the prop back a bit and then have the pilot use the electric starter,

 

[DisplacedTex]

What you saw was bumping the engine against compression. Turn the prop clockwise until you feel engine compression, keep turning just a little more and let go. The prop will spring back in the correct direction and start the engine, (with ignition turned on). I start my smaller rc model airplane gas engines this way. The problem with the rc single cylinder engines is sometimes it will start in reverse! I've seen some models get away from their pilots going backward!

 

[Joe Broady]

Recently The Great Waldo Pepper was on the Turner Classic Movies channel. Interesting how they hand propped the engines: pull the prop backward a fraction of a revolution then release. The prop springs forward and the engine starts. That's shown three times in the first 20 minutes of the movie.

Turner Classic Movies will air it again on Tuesday, August 18 at 1345 Eastern time (1745 UTC).

 

[PStickney]

What you saw was bumping the engine against compression. Turn the prop clockwise until you feel engine compression, keep turning just a little more and let go. The prop will spring back in the correct direction and start the engine, (with ignition turned on). I start my smaller rc model airplane gas engines this way. The problem with the rc single cylinder engines is sometimes it will start in reverse! I've seen some models get away from their pilots going backward!

I've used that method on full-sized (Well, Continental A-65s) on J-3 Cubs.
Among its advantages, it allows you to be standing behind the propeller, with easy access to the cockpit.
With an impulse magneto, (Where a clutch holds the magneto drive shaft against a spring, then releases it after about a quarter turn), you get a good strong (and retarded) spark, and its usually enough to get things running.