David,
There is no spindle bearing lube point. You have to take the quill out and apart to lube the spindle bearings. Done properly, a spindle lube job should last for years in a relatively clean environment. The manual says 10,000 hours interval for spindle re-greasing. Search on PM for posts showing my quills disassembled, and also search AlfaGTA's posts on re-greasing Deckel spindles, as that procedure follows the same rules about cleaning, cleanliness, grease type, and grease quantity. I strongly recommend you service the spindle if you cannot confirm that it was done properly within the last couple of years.
Given that oil pours out of the rack and pinion, I wonder whether you have a cracked or porous casting. The only path for oil should be via splashing onto the side of the quill when the machine is running. When stopped, no oil should travel up that high. I suggest you remove the quill, top up the oil, and see if it drains into the honed bore where the quill was before you removed it. Be ready to catch the quill as you crank the pinion downward; it will run right off the end of the rack.
By the way, both my F4 and F5 have screw plugs rather than zerks for oiling the vertical spindle housings.
RKlopp
P.S. I just realized yours is a round-head machine, and therefore older than either of mine. I have no manual for a machine that old, so don't how much of the above applies to your machine.