Olympus 35-105 zoom aperature control mechanism

[glenn_stauffer1]

I picked up a Zuiko 35-105 f3.5-4.5 lens on ebay and I'm not satisfied

with the way the aperature control works. If I hold the ring at 3 and

9 o'clock, the control is stiff and rough - it works through the

range, but not smoothly. If I hold the ring at 12 and 6, it works

smoothly. I have agreement from the seller that I can return it for a

refund, but, before I do, I'm trying to determine if the lens is in

need of repair or this is just characteristic of this lens model.

This particular lens is in nice shape otherwise and does not appear to

have been dropped.

 

Any idea what causes the aperature control to work like this?

 

Thanks, Glenn