RE: Pfalz DIII resources -- Photos, Drawings, Plans, etc.
Seth, you almost always need to prime gas engines when they are cold. After they have been run and are warm they usually start with out a prime. The choke is for priming the engine, if you have one. Most airplane gass engines have chokes.
Loctite is not something I would put on needle valve. That's just my opinion. I'm sure they have their reasons for doing it. Having worked for a Chain saw Mfg (Homelite) for ten years I never did it and never saw it done.