Deicer in fuel: Mooney POH recommendations

Original post: Feb. 28, 2007
By: Trey Hughes, Executive Director, MAPA

Replies: 1

> "I was told just the opposite by a mechanic--that
> Prist was approved but isopropyl was not."

From the M20K (252) POH:

To reduce the possibility of ice formation within the aircraft or engine fuel system, it is permissible to add ISO-PROPYL alcohol to the fuel supply in quantities NOT TO EXCEED 3% of the total fuel volume per tank. DO NOT add other additives to the fuel system due to potential deteriorating effects within the fuel system." Caps are Mooney.

The exact same quote is found in the M20M Bravo POH. The M20TN Acclaim is even more specific: "Ethylene glycol monomethyl ether (EGME) or other additives are not recommended due to potential deteriorating effects within the fuel system. Under certain conditions of temperature and humidity, water can be present in fuel in sufficient quantities to create ice formations within the fuel system. To prevent this, add anhydrous ISOPROPYL Alcohol to the fuel supply in quantities not to exceed 3% of total fuel volume per tank."

Regards,
Trey Hughes
Executive Director
Mooney Aircraft Pilots Association
210-525-8008

Revision: 10/28/2010