Sometime in the 1960s, the Japanese changed how they made backs. Instead of using a labyrinth design, they used foam to block light. While effective, the foam has a finite life and will need to be replaced.
Today, nearly all Japanese cameras (in truth, all), from the 1960s and 1970s will need to be re-foamed. There are inexpensive kits available on eBay. Or you can buy the material yourself and cut your own foam using a hobby knife. If you have many cameras to re-foam, it's less expensive to buy your own. What you want is a material from a craft shop, such as Michael's (in the U.S.A.). I've used the Foamies brand, which is sold in 9x11 sheets with self-adhesive backing.
European cameras use a different back design and will rarely have foam to block light.
It's simply a different approach. Think of how U.S., Japanese and European car makers produce vehicles for the luxury, performance and touring segments. Which is best? It depends on whom you ask.
When you replace your foam, I would recommend lighter fluid to help remove all traces of the old foam. Be careful to not allow foam to get into the shutter mechanism and especially don't let it get on an SLR's viewing screen.
I didn't read the previous reply closely. My fault.
Some cameras do have issues. For example, the Rolleiflex 35mm SLRs, particularly the SL 35 M/ME and E often have faulty electronics. The SL 2000 also is known to be unreliable.
I've seen some electronic issues with the Minolta XD and XG cameras.
I think that you can say that the simpler a camera is, the less likely it will have problems. That is a generalization, and there are plenty of exceptions.
I've had lots of mechanical issues with Petri SLRs. Maybe I just have had a bad run with them, or maybe this explains why they are no longer in business.
I've had maybe five or six Minox 35 models, and only one has a properly functioning shutter.
Yashica/Kyocera Contax models have been good for me, as have been the Yashica cameras that share the same mount.
Most Pentax K1000 models still seem to be working today, but for me the ME/ME Super has been an exercise in frustration when it comes to finding a working model. The Pentax MX has been a nice camera for me in terms of reliability.
I would just get a Canonet QL17 if you want a fixed-lens rangefinder. I see someone else mentioned the Petri 7s... and recently, I was asked about appraising one and got to test it out... it seems solid, so perhaps if you can find one of those, try it out. I'll probably go back to the client and buy it if I come up with the budget for extra equipment.
Thanks for the replies. The Canon 17, here in UK, is up in price compared with Yashicas and Minolta RFs. I have also been looking at the Konica S2, besides the Petri models. There is a Petri 7s on ebay UK, which has been recovered in lime green leather. It looks astounding, and the price is already up to £42.00 on bids. The Yashica Electro 35 was my first RF, followed by the Minolta Hi-Matic 9; the the Yashica MG1. I have been quite taken by their feel and appearances. Perhaps after 1 more RF I should call it a day, otherwise ........ ?
Something else to watch for, the Hi-Matics were known for developing a loose lens barrel to body joint. This is not a simple fix. My Hi-Matic 9 is just starting to get that way, but it still shoots crisp and clear. My Electro 35 GSN still has the original pad and its doing just fine. I actually went inside to replace it at the same time as the rest of the seals but it was perfect. The lack of the thunk in yours I a simple adjustment of the rod under the bottom cover. It can be a bit fiddly getting all three movements synchronized with just two adjustments, but its not difficult. Go slow and listen carefully when adjusting.
The C35 is a nice and compact little camera as well. Should still be found under $40 if you look hard enough.
I have an MG-1 bought it around the same time you did on ebay for around £50,
bought the camera and then went to Yashica Guy's website to buy a battery adapter
and started reading about the pad of death, I definitely don't have the patience or time
to fix such a technical issue like that. Luckily my MG-1 doesn't suffer from the pad of death
but I would say if your going to buy off ebay then yashica's in the electro 35 range are
a bit of a risk, should be fine though as long as the seller claims it works properly,
if it doesn't you can probably claim a refund stating the seller hasn't listed it properly.
Anyway great camera, definitely a good bargain for £50, just a bit hit and miss