With the F, the lenses were labeled, "Auto," in reference to the fact that the lens will meter and allow you to compose at full aperture, but then stop down to the set aperture immediately before the picture is taken. It's one of the features that made the F so unique. However, this means that unless you were shooting wide open, the meter would receive far more light than the film would, so the meter would have to compensate for this in its readings.
Before 1977, lenses coupled to the meter using a set of forks that stuck out of it and engaged a pin on the camera. Post 1977, Nikon introduced AI lenses, which skipped this and communicated via a feeler that engaged the aperture ring. Either way, however, the camera's meter must know the set aperture in order for the meter to work properly.
When you cross-mount like that, the camera has no way of knowing what aperture the lens is set to. To get around this, you have to meter the way it was done before the F: by setting the lens to the taking aperture to meter. This is done by actuating the depth of field preview.
In short: those lenses will only meter properly when the depth of field button is depressed.