enginehistory.org

[rhaus]

I am wondering when ADI (anti-detonant-injection) first came into use. I have a theory that it was NOT originally used in aircraft engines. My reasoning for this is that I recently added a 1917 Fairbanks-Morse 3 horsepower engine to my hit-and-miss engine collection. This engine is ignitor fired (make and break ignition) but it is actually throttle governed, rather than true hit-and-miss. It has a dual fuel carburetor on it so that it can burn gasoline or kerosene. But perhaps, most interestingly is that it also has a needle valve in the water jacket with a tube leading to the intake port, when opened it functions as a crude water injection system for use when running on kerosene or other low octane fuel. This way they did not need a lower compression ratio to accomodate the lower grade fuel. I am fairly certain that this was not new, even in 1917.....so I suspect the idea did not originate with aircraft, but with stationary farm engines.

thanks,
rh

[jjuutinen]

Not the answer per se, but ADI was fitted e.g. to a Soviet pre-WW2 artillery tractor in which it was used when running on lower quality fuel

[rhaus]

thanks! ...I would not have expected it to show up in pre-ww2 tank engines.....but then again, I sure did not expect to see it on a ww1 vintage stationary engine either. Perhaps this is a far more common practice than first thought.

[gwhite]

Ricardo makes mention of water injection in a two stroke prior to WWI. Howevr, ADI did not enter common use until WWII.