ORIGINAL: Aiden88
The dreaded <u>“hydro-locking”</u>. Often mention is the term “hydro-locking” with inverted engines. It is easy with an inverted engine to get the piston full of fuel and it will be difficult (or maybe impossible) to turn over the engine by hand and application of a strong electric starter may damage the engine.
Right, that's where tank height differential comes into play...
Having too much offset will lead to siphoning, but that is a completely different problem.
All too often improper plumbing setups will flood the engine during fueling, and novices will blame the tank height.
I have a couple of planes with inverted engines, that I must clamp or close the fuel line while fueling to prevent hydro-lock upon trying to start the engine.