Yashica Mat EM TLR - Shutter keeps sticking

[jopkonica]

Hi all,

Just got a Yashica Mat EM TLR that I can't keep the shutter from sticking. It's been "used and abused" and not worth doing a professional CLA... so I've flooded the shutter with naphtha numerous times and the shutter will work for a few minutes... then seize back up. Usually I can free a shutter for good with one or two doses of naphtha... but this one has had 8 or 10 generous doses and still sticks. Any ideas? Thanks much!

jopkonica

 

[oftheherd]

I have a Fuji Six that is like that. I am guessing there is just so much gunk in there that I am going to have to remove the lenses for a very thourough cleaning, or maybe even take the shutter out for a complete bath and re-lubrication. Could that be your problem as well. That EM would be not much younger than my Fuji Six I think.

 

[Dan Daniel]

Are you doing the floods with the shutter in the camera? If so, you might need to be prepared to remove it. Sometimes a shutter needs a couple of days of soaking. And also some strip-down to expose the escapement and such to more real flushing.

And unfortunately the shutters on earlier Yashica-Mats have been a consistent source of problems for me. I've overhauled maybe fifteen 'Mats, and have four or five shutter blocks that I could simply never get working again. Be prepared. Then again, the nice thing is that the overall design of the cameras barely changed over the years so I have also made a few Franken-Mats that work well. Keep your eyes open for donor bodies.

 

[Landshark]

Flooding works, sort of. Also swab it out with Q-tips or the like. Another possibility is liquid remaining on the shutter blades. The mainspring can't overcome the surface tension to release.

 

[rick oleson]

The basic problem is that you're dissolving the gunk but you're not removing any of it from the shutter. When the naphtha evaporates, the gunk is still in there. If you have ENOUGH solvent, like say you dunk the shutter in a pint bottle of it and leave it there for a day or two, it will dilute the gunk to the point that the shutter will work. Otherwise you need to do something to remove the dirt. With the front panel off, spraying the works with a generous amount of CRC QD electronics cleaner or something similar, and letting it pour out the front, will flush out some of the dirt. To do a really proper job, it's best to remove the escapement, the blades and their actuating ring (which generally entails disassembling the entire shutter), cleaning the individual parts and reassembling when every part is clean and dry.

 

[Moto-Uno]

Owning a few YashicaMats , I can say that it's not that onerous a task to remove the
lens from the shutter and soak it as suggested previously and apply a trace of lube where you can. The camera is worth the effort as the results will speak for themselves. Peter

 

[jopkonica]

With the front panel off, spraying the works with a generous amount of CRC QD electronics cleaner or something similar, and letting it pour out the front, will flush out some of the dirt.

I've actually got a can of CRC QD contact cleaner on the bench. Never even thought of trying that. I'll blast it out tomorrow and report back how it went. Thanks!

jopkonica

Update... The CRC QD contact cleaner worked! I sprayed three generous amounts into the shutter over the course of a day and the shutter has worked consistently since. The shutter also has less drag and operates much smoother. I think I've made a $10 Yashica Mat "basket case" into an actual shooter. Thanks very much for the tip!

 

[mikemc_photo]

Well silly me....All the shutters I cleaned, you need to lubricate. I use molly powder and neolube on the blades and operating ring. the escapement needs to be flushed and mollied , worked and blown out. a dab of molly grease on the main cam, then run the shutter w/o the speed cam, you should get a good high speed if your M/S is good

Removing the shutter is a quick job, you really cannot clean a leaf shutter properly in camera Another thought on the copal shutter is the m sync section is dirty...set the selector to x The Copal shutters were quite good speeds wise vs Compur due to the M/S wire on the Copals, didn't stretch like the Compur