This 124G may not be worth saving...but if I could clean the spiderwebs out of the lens, it would be a great backup to my Rolleiflex. Does anyone have any ideas on how to remove and clean the Yashinon taking lens? Is it something that a non-professional repairman (that is I) could/should do? The shutter and meter both work and the film transport is OK.
The viewing lens and taking lens are not interchangeable. While the taking lens is a four element, the viewing lens is a three element. I have taken apart a yashinon lens on a Yashica D. If you are really lucky, the fungus may be on an exposed surface and therefore accessible for cleaning. If the fungus is between the lens elements (in the canada balsam that cements the two front elements together) then you are SOL.
The Yashicamat 124s commonly get spots of oil from the shutter on the inner elements. Are you sures it fungus or oil. If oil, its a fairly easy clean, if you have the right spanner wrenches. Even if you go, I recommend sending it to Mark Hama for a CLA. These are great cameras for the money.
Yes, you are right, they are different lenses and in fact maked as "view" but that doesn't mean it can't be done. You have to swap both the front n rear cells, then adjust it to focus to the film plane to match the screen.
I'll pull mine out later to see if the threads are different but I doubt it.
Here is a site that you may be interested to see how to access the inards of your 124... Dead Link Removed
If you want to browse the other camera repairs on this site check this link... Dead Link Removed
I'd say send it over to Hama, its a good price from a reputable man, but if you're going to try yourself here is a good qaulity assembly chart for the Mat 124g.