I’ve had a Minolta-mount Soligor lens that I received in a package deal a while ago, so recently I bought a Minolta SR-T 101 body to go with it. I bought it on ebay, untested/for parts/not working (but dirt cheap), as is my habit. When it arrived, the mirror was not flipping up, and doing some dry tests with the lens (which I was now able to mount on an albeit non-working body), found out that the lens was not stopping down. I Googled the mirror problem, and according to this service manual, the two common reasons for this problem were related to gears either near the mirror itself (involving popping off the lens mounting barrel) or near the shutter button (involving taking off the entire top of the camera). In a fit of extreme optimism, I actually did pop off these components, then immediately panicked upon seeing such Swiss-watch-esque inner workings and I hurriedly put the covers back on.
So after letting the camera and lens lie around my apartment for a month, I took a closer look at the mirror and noticed that there was a little post on the side that really wanted to be in a hole on the side of the mirror. So I slightly forced the mirror so that the post was in the hole, and magically the mirror worked!
So now with my confidence bolstered, I decided to tackle the lens’ stopdown problem. This involved actually taking the lens apart a bit.
See that lever? When you turn the aperture ring it turns the lever. That lever in turn is supposed to push on this other lever, which actually controls the aperture blades.
The problem with my lens was that somehow the first lever hopped onto the opposite side of the second lever, so it wasn’t moving it at all when the aperture was changed. Reassembled it correctly, and now it works!
So there you have it, an perfectly functioning Minolta SR-T 101 and Soligor 70-150mm f/3.5 for $20!
More recently, I once again ebay’d a “non-working/for parts” SR-T 102 simply because I wanted the 50mm lens that was bundled with it. Imagine my delight when I received it to find out that the body worked perfectly fine too! Or so I thought. After I put my first roll of film through it, there were a couple of shots that were overexposed waaay at the right side. A friend of mine correctly diagnosed this as an incompletely closing rear shutter curtain, which was only happening at slow shutter speeds. I figured I should lubricate the rear shutter gear, so I cautiously opened up the bottom (because the top is just crazy Swiss watchy) and actually found the gear that wasn’t turning the entire way at low shutter speeds.
But how do I lubricate it? I’d have to get to the other side of it … how? Anyways, I dropped a bit of oil on top of it, which of course didn’t work. I was resigning myself to junking it when I came upon Mike’s Hobby Site, some sort of Geocities-style website from the 90’s. But he has some weird, not very informative (well, without an engineering degree) guides to repair random stuff, like Minolta SRTs. I’m going to steal this picture off of his site:
See that gear labeled “2nd shutter”? That’s the gear that controls the tension of the second shutter spring. Ignoring his caveat to use a shutter speed tester, I just increased the tension until the second shutter closed all the way at slow speeds. Camera fixed! Thanks Mike!!