I recently bought a Jupiter 9 in Contax mount from Yuri Boguslavsky of Fedka.com. It was at a significant discount because there was a problem with the mount. When mounted the lens would be at infinity, but the body would need to be at 2.5 meters for the rangefinder cams to engage. While I could use it "as is" in scale focus mode, that kind of defeats the purpose of having a coupled range finder. So I pulled out my Jupiter-11 and compared how the mount looked on it to the one on the Jupiter-9.
The mounting ring was turned slightly counter-clockwise (as viewed from the front of the lens) out of alignment. The ring has three small screws on it. After removing them, this turns out to be an outer ring that slips off when the lock is held open. Under it are three set screws that hold the mount to the lens barrel. Removed the set screws and then slowly twisted the mount so that the red dot is in alignment with the focus mark and the rangefinder cam as it is on my Jupiter-11. Put the set screws back in (after dropping one...
Yikes, they're tiny! Glad I have hardwood floors.). Put the ring back on and put it's screws back in. Mount the lens as normal and now it "just works" as it should.
I'll need to burn some film to be sure, but it looks like I've got a really nice Jupiter 9 for a good price.
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Playing and learning daily with: 4x5 Crown Graphic, Leica IIIf w/ 50/2 Summitar, Nikon F2 Photomic w/ 50/1.4 & Olympus E-PL1.
"Some people are 'the glass is half full' types. Some people are 'the glass is half empty' types. I'm a 'the glass is full of radioactive waste and I just drank half of it' type. And I'm still thirsty." -- Bill Mattocks