The primer line should come off the gascolator or somewhere upstream of the mechanical fuel pump. It will not come off the engine itself.
So if I understand correctly, the priming system will take fuel from the gascolator, and pump it into the carb? (why is this necessary in cold weather?)
But why then does the O-320 manual depict a port for the primer on the engine itself? Is this an older way of doing it?
Don, I'm confused as to what thousand words your picture is telling me, other than that your engine has some fitting where a fuel pump would go...
The fitting you see with the 1/8" copper lines coming off of it is the primer connection that as Mel said comes from the primer pump. ... I am pretty sure since you can't find it, it is not installed on your engine.
The primer pump, is your electric boost pump that's in the cockpit.......
Thanks! So does it appear that I have those two ports correctly labelled in the photo?