Magna, the blower has a gravity drain for the oil in the gearcase. Excess oil drains off via gravity. However, these chambers where oil accumulates when it leaks past the seal don't come out straight down, they're like cast into it and come out of the top. That's why it requires constant vacuum as it has to lift the oil to get it out. I'm not sure why the designed it the way they did but that's how it is.

So the mechanically inclined would tap on the low spot then and plug the high spot. :D comeon now or is the case to thick or fubarred to be done up like that? It would save the weight of a vac pump and extra resevior etc + be alot simpler.

Perhaps, but I'm pretty sure they did it that way for a reason. I don't know why but those ports are notorious for clogging even with a constant source of vacuum on them so I wouldn't want to change it to gravity only even if it's possible.