Anyone know about Mamiya RZ67 lens floating element ring?

[Lou Jost]

bMaybe someone here can help me? I've bought a potentially nice set of Mamiya RZ76 lenses for close-up photography. These lenses have a blue rotating ring that supposedly moves floating elements. The photographer focuses, reads the distance scale, and then manually sets the floating element rig to that distance.

The problem I have is that of my three lenses, only one (the 50mm ULD) has a ring that shows some resistance, as if it was moving some optical elements inside. The blue rings on the other two (250mm apo and 140mm macro) turn without resistance. On the macro lens there are also no detents so you can turn it around and around forever. The 250mm lens has four mild detents that lightly click as I turn pass them, but they don't stop the ring, which turns forever like that of the macro lens.

I don't think the rings on these two lenses are functioning properly. I can still return them in the next day or two if they are not functioning as they should; the ebay sellers claimed the lenses were fully functional. Does anyone know how the floating element ring should behave on these lenses? Any help would be much appreciated. Thanks in advance!

Edit: I see that there is a second ring on the macro, which moves internal elements. So I guess that one is fine. But there is only the one blue ring on the 250mm apo, and it doesn't seem to do anything.

Edit 2: Aha! The blue ring that I thought was the floating element ring is only a depth of field scale ring! There has to be another ring marked "Floating system" in order to adjust the floating elements!!! The 250mm apo lens that I bought is an older version that doesn't have floating elements.

I will leave this post here in case others some day make the same mistake as me.