That's been my experience, too. Answer: the engines are tilted and even at the best of times, the drain at the bottom or even a dipstick method just won't get it out. Don't sweat it.

I was also about 3.5 - 4 on the last change. (all changes for that matter) Would have made too much sense to put the drain hose at the lowest point.

Jack,
You have to remember that these engines were originally designed for a tractor (Kubota), where the engine is level, and not inclined as it is in our boats. The original designers got it right. I have heard of some owners, during a rebuild, welding shut the current oil pan drain, and locating a new one further aft, at the lowest point. Seems like a lot of work to me. I just accept the fact that I will never get all the oil out when changing it.

Tom,

I know...just a little venting on my side. That being said the plus side is that it is a fairly simple engine to maintain for the DIY sailor and parts are readly available from multiple sources.

I agree that relocating the drain would be a lot of work and there are much better places for "boat bucks." I would probably install a gold plated pump handle on the head prior to relocating the oil drain in the engine, just to give an idea of how far down my list this modification sits.

It is what it is and a little oil left in the pan is not the end of the world.