There is such a wide range of Navions out there, to make a decent suggestion we need to know what you're looking for in a Navion, Engine, Fuel Capacity, Equipment, mods, paint/Interior etc... What is your intended mission for the airplane? Local VFR to pancake breakfasts and static display at fly in...

Hal,

Where do you drain the fluid at? (To get it all out) And how do you replace it? (Mule or just filling the reservoir back up?)

I was wondering if there was a good flush procedure on this as mine hasn't been changed in 30+ years

~Erich

Just so you know, I/Burlington Air Center at KBUU is now an STEC dealer and can handle your 55X installation. Give me a call, 262.763.9500 ~Erich