If I don't fill it up past the tank neck, all is OK
Same thing on my old 12. The 14 can be filled to the bottom of the cap. I have a screw-in cap now, so I can squeeze in a little more, if I'm careful not to splash. Some pumps flow a bit slower, or have finer graduations of flow with the trigger, making it easier. When I filled up the 12, a minute later it would piss out a puddle through the overflow.
It may be a pig, but it's a pig with a rocket in it's ass!