[burtj]

I pulled my cowling to prep for pinhole filling, and noticed that the mixture arm nut hits the lower cowl (AFP injection, Superior cold air sump, IO-360). The nut rubbed through the inner fiberglass layer, but hadn't penetrated the outer skin of the cowl. I was able to re-index the mixture arm aft two teeth, but to gain a bit more clearance want to invert the mixture arm bolt (head down). Normally I know that it's "heads up", but I'm not sure if that rule is set in stone. Thoughts???
Burt

 

[ChiefPilot]

It's a guideline, not a hard and fast rule. Given the choice between rubbing against the cowling or being upside down, an upside down bolt would win every time on my plane.

 

[David Paule]

It's acceptable. Make sure it's safetied well.

Dave

 

[BobTurner]

I think most people know the story of the upside down bolt on the nose gear of the Piper Arrow, and the well meaning mechanics who put it "right side up".