Jupiter 9 focusing issue

[eSFotos]

I bought a Jupiter 9 85mm f2 for my Zorki 4. Looks okay and I paid next to nothing.
However it came with an issue. The focus of the lens doesn't match the viewfinder.
Does anyone know how to adjust the cam.
cheers
Ed

 

[Sonnar Brian]

The optics module unscrews from the focus mount, and uses shims. If the focus is behind what the RF indicates, the shim needs to be thicker. If the focus is in front of what the RF indicates, reduce the shim. The later Black J-9's have a secondary shim for the rear optics. If you cannot get it to work by adjusting the main shim, you may need to adjust the secondary shim as well.

 

[eSFotos]

Thanks but that's not the issue.
The issue is, when the lens focus is set at infinity, two images of the rangefinder of far away object do not coincide. I know it's not the camera because it works perfectly with other lenses.
It seems that the rangefinder cam does not protrude long enough.
I know I have to dismentle the lens but what I want to know is how can I adjust this cam.
How far this cam must protrude?

 

[Sonnar Brian]

I do not know how the Cam can be adjusted out.

Best instructional that I know of:

http://pentax-manuals.com/repairs.htm

http://pentax-manuals.com/repairs/j9service.pdf

On a J-3, the issue that you are having can be corrected by screwing the entire helical deeper into the mount. On the J-3, I take off the focus ring to reveal the screws that hold the helical into the 39mm mount. Screwing the helical in further allows the Cam to protrude out farther and drive the Camera to infinity. Might be the same on a J-9.

 

[Krosya]

Looks like your J-9 was put together wrong. Second link that Brian posted is what you need to fix the issue. Its doable but take time and patience. I have done it before with success.

 

[eSFotos]

Thanks Brian, J9 Service is perfect. Also thanks for that repair site. It's awesome.

Krosya, thanks. I will have a go at it.

 

[wolves3012]

It's a fairly common issue for J-9 lenses in LTM to have been dismantled for a re-lube and put back together wrongly. I believe it just takes patience to get it back right! Never taken one apart myself but I think I'd make plenty of notes and be marking everything.

 

[eSFotos]

Thanks Wolves,
Brian's 2nd link explains how to dismentle and more importantly how to put them back correctly. Excellent article. Copied to my library for the future reference.
cheers