OM-2n: aperture-camera communication problem

[HuubL]

Hi,

I hope there are still classical film OM aficionados that could help me with this problem I have with my recently obtained OM2n. With a lens mounted onto the camera, the set aperture doesn't seem to communicated to the body. Changing aperture in manual or auto mode doesn't change the position of the meter needle. Changing the speed in manual mode does result in a stepwise moving of the needle. The obvious lever that would sense the lens setting that I feel could be responsible for this is indicated by the arrow in the attached image. This lever (if it is the responsible lever) seems to be stuck and it seems to be marred also, maybe by the movement of the corresponding lever of the lens. Would anybody have any idea about fixing this myself? Is there anybody willing to make a similar photo showing the normal situation, so that I could determine how the lever should be positioned?

As a Leica M and Canon FD SLR enthousiast I'm really impressed by this little Oly that I got it two weeks ago. I had to wait for two weeks to get my lenses (Zuiko 50 1.8 and Zuiko 100 2.8) and I hate it see that my new system doesn't seem to work as it's supposed to. If the camera is broken beyond repair, which I don't hope, because it's in a really nice condition, I'll probably get myself another OM body (OM-1, OM-3??).

In any case, thanks for your help!

Regards, Huub

PS. I posted this also on the Photo.net Olympus forum, but I have the impression that, even for an evil SLR, I got a speedier response here 😉

 

[Richard Ross]

Hi Huub

That is indeed the relevant lever and it should move freely. Its normal position with no lens mounted is adjacent to the red dot on the lens mount, which corresponds to minimum aperture. With a lens mounted, the little pin on the back of the lens engages with this lever and turns it progressively clockwise (as you look at the camera throat) as the aperture is opened.

If that lever is stuck where it is on yours the camera will be thinking the aperture is permanently open which is why you're not seeing any change with aperture setting.

I don't know if that's a diy job I'm afraid, but if you want to try unsticking it, push it anticlockwise towards the red dot and see if it frees off.

Hope that helps

Regards
Richard

 

[FrankS]

I have the same issue with my Nikon F4. I noticed that my 50f1.4 lens has oil on the aperture blades, so I'm thinking that the drag caused by the oil, damaged the aperture stop down mechanism in the camera, because other lenses also remain wide open during an exposure even when they are stopped down to smaller apertures. I got an estimate for $150 to fix this issue on my Nikon body.

 

[Trius]

John should be around shortly to help. If it's anything more than a bit sticky (either actuation lever or slow aperture blades), I'd say leave it to a pro. No use screwing up an OM if you don't have the knowledge/skills/tools.

Does it happen with more than one lens, assuming you have more than one OM mount lens? If you don't, perhaps borrowing one for a test could be arranged.

 

[HuubL]

Thanks for the response guys. It isn't the lens, it happens with both lenses and the lever is really stuck. Absolutely not a hint of movement upon even a firm push in the closed direction. I'll see. I got the camera for free and don't want to invest to much money in it to get it fixed. I'm not double left-handed and have opened up (and fixed 😉) a number of mechanical cameras, so perhaps I'll try my luck on this OM too. Anyway, thanks again. I'll let you know what happens...

 

[Richard Ross]

The Olympus Hardware Resource pages should have an OM-2 manual, but for some reason I can't access them this morning:

http://olympus.dementia.org

 

[hans voralberg]

The shutter speed ring mechanism underneath the bayonet mount (which you have to open to get to that lever) is quite (if not extremely) complex, so take care not to mess it up, I think there are 1-2 springs there and they do fly out.

Why not PM John Hermason here, shouldn't be too expensive.

 

[Trius]

I've never understood the logic of "I got it for free so don't want to invest a lot in it." It seems to me the criteria should be what the camera is CAPABLE of once fixed, how valuable that might be to the owner, etc. As well, since there has been zero investment so far, that means less total expenditure to have it working.

 

[HuubL]

Thanks Richard and Andrew for the link to the olympus.dementia website. Unfortunately, I couldn't access the website yet, but I'll keep on trying. Maybe a personal server that's not on line all the time.
Hans, I did open the mount yesterday evening and even got the speed selector ring out without loosing the little clicker ball 🙂)), but that still didn't solve the stuck lever. I inspected the cabled aperture ring and that indeed looked a little complicated. Because it was too late to continue I decided to put everything back together again and was successful with that. At least, the shutter speeds are still ok. Maybe I'll try again tonight and go one step further. I'll use a digital to make images of the various stages of dismantling. Could be helpful with reinstalling.

Andrew, indeed the mirror bumpers have mostly deteriorated and I did already clean the focusing screen. I had ordered foam from Jon Goodman to replace the goo and that also arrived yesterday. Do I understand correctly that the prism is packed in foam as well? That would mean that I have to remove the top of the camera to replace it, not?

 

[hans voralberg]

Yes the prism is covered by foam on the back side, both side, can only access it with top off. Be careful cleaning it or you will wipe the black anti-reflection pain on the prism as well.

 

[HuubL]

I've never understood the logic of "I got it for free so don't want to invest a lot in it." It seems to me the criteria should be what the camera is CAPABLE of once fixed, how valuable that might be to the owner, etc. As well, since there has been zero investment so far, that means less total expenditure to have it working.

Earl, you're right of course. It is only that I probably wouldn't have had the camera if I hadn't got it for free and now that I have it, I feel it would be no big loss if I could not fix it myself.

 

[ZeMane]

Hi Huub,

I got a very similar problem with my OM-4Ti. Instead of being stuck, my lever moves freely. Brought it for being serviced here in Madrid but the technician could not find a replacement.
The fix consists in replacing a wire attached to a spring, which is broken, so that's why the lever moves freely.
Maybe your OM-2n have some problem with that wire too...
In the meanwhile, I recently got an spare OM-4 which will "donate" that wire and any other replacement needed in the future.

Once you have already got two Zuiko lenses, I think you could try to service that OM-2n, since I'm really sure you'll love it once you start to use it.

BTW: let me know if you see for sale there a second hand silver Bessa-R + half case + Jupiter8 + vented hood + APX100 loaded... Lost it past April in Amsterdam... damn!!!!:bang:

Cheers,

Zé

 

[HuubL]

Thanks again Andrew. I got a reply on Photo.net also. John Hermanson, THE Olympus camera repair man personally explained how I could approach the problem. This is where I'm now (copied from my reply on Photo.net):

Thanks John. Wonderful to find your response here. With your helpful comments I was able to release the aperture coupling ring back to its original position. After fiddling a little bit with getting the timer ring aligned again with the gear wheel to get the shutter times back to normal, the camera is almost functioning like it should be. The aperture ring now goes clockwise with opening the lens, but it doesn't get back yet because there's too much friction for the spring to pull it back. I have to take off the lens and push the lever back to the closed position manually. Problem is that the ring isn't circular anymore, probably because it was stuck in the "open" position too long and got deformed. I understand the camera has not been used for at least 15 years. The camera belonged to a lab where it served as a microscope camera. When it no longer made good pictures it was put aside and a new Oly 2SP was bought.

I'm hoping the ring gets back its original shape with some time on the shelf and will ease up a little. In any case, I'm going to keep my eyes open for a cheap, broken OM-2 for a replacement ring.

Anyway, thanks a lot for your excellent help.

The last thanks holds for everybody here as well! This is a wonderful environment and I'm proud to be a member.

 

[John Hermanson]

Once the ring is damaged (from lens turning too far when the stop screw is missing), it's not going to fix itself. Sometimes you can reverse-bend at the high point but you risk breaking the ring completely. Best fix is to replace the ring. It has a meter string super-glued into a tiny slot and has to be glued into the new ring at the same spot without letting the glue wick along the string. You'll lose meter timing when this is done. You also have to keep the string on the pulleys and since this one is spring loaded, you can't let it go cus it might disappear inside the body. John www.zuiko.com

 

[HuubL]

Thanks again John. It's only now that I see your response. Indeed, the camera didn't fix itself and installing a new ring myself looked a bit too challenging. I decided to send the camera to an OM repair man in Germany. Sorry to not make use of your services, but the extra cost involving shipment back and forth (and the problems with customs when it would arrive back in Holland) would make it too expensive.

I'll keep you all posted here for when and how I get my Oly back. I hope soon, my two Zuikos are screaaming for an outing.

 

[John Hermanson]

I'm sure you'll find a good service guy in Germany. Good luck! John

 

[HuubL]

It's back and it's wonderful. Frank Timman put a new metal aperture simulator ring in and CLA'd the camera. It's now sooo smooth... Tomorrow I'll load a roll of film...