Olympus Pen F's with stuck mirrors?

Hey guys.
So, I have a chance to buy what appears to be a very minty gothic Pen F. Everything works fine except the mirror seems to get stuck when a lens is attached. I've come across quite a lot for sale with this issue, otherwise the camera works just fine without the lens attached.
Is this a common issue with the camera? Can the problem be fixed relatively easy?
Thanks
-stuart

Well, I has a similar problem and I'll tell you what I did. It may not help your camera but it's easy and probably won't make it worse.

I removed the bottom plate of the camera and observed the action of the mechanism as I cycled the shutter without a lens mounted. It looked grimy. I dribbled some Zippo lighter fluid into the levers and gears and a lot of gunk and dried lube came out. I then relubed the bearing points with some very light weight machine oil, at least as well as I could without disassembly. The camera has worked fine since.

Don't know if this will help your problem but it might be worth a try.

This is a known issue with the original F's. I've got one like that now. I recall reading long ago that fiddling with some bit of the linkage would free it, but don't know the details.

I'm glad that I stumbled on this thread. I'm helping a friend of mine liquidate his collection before he passes away and he just gave me a Pen F and a Pen FT to put on Ebay. The FT works perfectly and I need to get it listed before I'm tempted to buy it myself as I've done with about $500 worth of his other gear. The Pen F has a mirror that sticks. This one however sticks with the lens on or off. I wonder if this is the same problem just worse.