Olympus Zuiko OM 28mm 2.8 lens – slow aperture blades. Easy fix?

[Roundabout]

I have an OM Zuiko 28mm f2.8, which has problems with the aperture blades. When I press the button on the side of the lens (depth of field button?) the blades seem to close slowly. They then stick for a bit, and then slowly open. My other Zuikos 'zip' closed and open instantly.

Also, when adjusting the aperture dial, the blades seem to half close and then open on their own. The other Zuiko lenses I have, don't move at all when I adjust the aperture.

I have a great repair person, but it would probably cost me as much to get him to fix this, as it would to buy a decent version online – it's not the most expensive lens in the world.

So, despite the fact that I have never attempted a camera or lens repair myself... how hard would it be for me to open this lens up and fix this problem? Or am I asking for a world of pain?

Thanks for any tips, step by step guides, encouragement… or otherwise.

 

[vysk]

Yeah, easy fix. The mechanism is spring tensioned, and the lever arm very likely has oil on it. If you search the web, you'll find that it is a very normal failure for the age of the lenses.

To fix it yourself, take the screws off the rear mount. You'll see the mechanism and spring loading. Take the lever and spring off, clean it all up with lighter fluid (naptha) and put it back together. Some suggest leaving it dry; you can also use a tiny amount of shutter oil.

 

[vysk]

http://www.youtube.com/watch?v=lfkubKK15Uk

Dead Link Removed

 

[Roundabout]

Thanks vysk. Much appreciated.

I'll have a go at this when I'm more awake.

 

[Roundabout]

Hmmmmm. That YouTube video seems to be a bit wrong. There doesn't seem to be anything wrong with the lens.

 

[sagai]

Yes I agree, that video is about how to disassemble an otherwise perfect lense.

I have just done however my fix for the same lense with the same sympthome.
Takes 5 minutes to fix it. All we have to have a proper screwdriver.
There are two black metal circular platforms when we take out the three screws and the one that fixes the back metal plate to the black back lens holder (4 screws! , the last one should not necesseraly to be taken fully out, otherwise there is a little game how to reinstate later that tiny little screw). When we have these twoes, there is an oil inbetween them, so little bit of alcohol (I had a tiny bit of palinka to be sucrifised for this purpose ) to clean it.
Yes, there is a spring too, careful, not to loose that and not to forget to reinstate at the end.

Cheers!

 

[John Koehrer]

Generally it's the easiest SLR lens to clean of slow blades.
Once in a blue moon you may find one with oil in the blade housing. Few and Far between though.

Just pay attention to how the rings are assembled. There's only one right way.

 

[sagai]

I think it is about slow reaction to DOF due to oil between these circles.
Blades are however could be more complicated to be cleaned.
http://olympus.dementix.org/Hardware/PDFs/28mm_f2.8.pdf