Yashica Mat-124 G Stiff Dials/Buttons & Light Seal Replacement

[lanuitamericaine]

Lifelong photographer, but new to the repair forum, so hello to everyone!

I'm just making my first foray into medium format (having been a 35mm user for 30+ years, mainly with Pentax SLR/Leica M).

I have been kindly gifted a Yashica Mat-124G, which seems to be in relatively good condition although not used for years, as far as I can tell - cosmetically good and with seemingly clear lenses. Shutter speeds at least sounding fairly good (only based on what a Leica M sounds like at different speeds, which is my only reference for mechanical cameras).

Two things I've noticed initially which I'd like to attempt repairing/replacing, if anyone would be so kind as to provide a little guidance -

Firstly, the little dials which control Shutter Speed and Aperture are very stiff indeed. I'm guessing this is grease which has turned hard over years of non use, but have no idea where to lubricate them. Also, although the shutter seems to fire OK, the shutter button itself sticks in the firing position, then returns slowly before finally popping out - again, I'm guessing a lubrication issue?

Secondly, it appears to me that the light-seals around the door/hinge have flattened/disintegrated over time. I understand that there is a seal between viewfinder and light meter on these also (guessing you remove that by taking out the 4x little screws around the VF). Is this just a matter of carefully removing the old residue and then replacing with some kind of repair kit? If so, is there a known good source of such kits in the UK, please? With the price of 120 roll film these days, it seems prudent to replace these before wasting film & processing should there be a leak.

Many thanks in advance - very excited to try this camera and my first medium format roll!

 

[Kino]

Hello and Welcome!

You have a lubrication issue, but it is NOT an issue that you can cure by simply applying lubrication over the old, petrified grease.

When wheels, levers and gears start binding, it is usually due to solidified grease. This grease must be removed with suitable solvent and then replaced with a proper type of grease, but VERY SPARINGLY.

If you've never seriously attempted a repair before, you shouldn't start out on an expensive camera you really want to keep and use.

Seriously, if you want to start making camera repairs as a hobby, go find a camera you wouldn't mind destroying and try your hand at that.

For a Yashica Mat-124G, with the prices on these cameras reaching absurdly high premiums on the used market, it would be worth a formal repair at a known repair shop.

Just the cost of purchasing all the proper tools and supplies to make good repairs will come close to a basic Clean. Lube and Adjustment, so I suggest you spare this camera and find another to launch your repair journey. Some people find out rather rapidly it isn't all that much fun and wind up with a bag of parts and a bad experience.

You could do the light seals easily enough, but the rest of it is best left to a repair person.

Just my 2 cents.

 

[lanuitamericaine]

Hi and thanks for the reply!

I see your logic on prices. However, this camera cost me nothing, it was just given to me by a friend having a clear-out, so I don't in this case feel like I would have lost anything by giving it a go. I used to send my Leica's out for professional CLA, but they were considerably more expensive than this! To be honest, if I were going to spend CLA money on it, I would just put that towards a different MF body with interchangeable lenses.

I'm pretty careful and have been restoring vintage hi-fi for years, as well as cars. I know that's not cameras but I've not broken anything yet. As long as I have reasonable instructions and any particular warning points to watch out for, I think I'd be happy to at least give it a go.

Thanks again.

 

[DWThomas]

I second Kino, mine had some obvious problem with the switch that enables the built-in meter when the hood is opened. I found some info and looked into it, but though my ancient working career included some fiddling with jewel bearing analog meter movements, I decided not to jeopardize a camera that was optically and physically quite excellent. I used the camera for a number of years with an external meter (some claim the built-in meter wasn't/isn't all that good anyway).

During an outing on a cold day I began to experience that slow-to-return shutter release a few years back and, living in the US, sent mine to Mark Hama in Georgia for a CLA. It came back with the meter working and re-calibrated to use a non-mercury battery, a neat little black Fillister head screw tapped into the front panel to prevent bumping the flash sync to 'M' (useless with electronic flash and can lock up the shutter if you attempt to use the self timer with 'M'), and the opening latch and other mechanics smooth and working like a new one. Between the original purchase (in 2010) and the CLA (in 2018) I've invested over $300, but that would barely even cover a lens for some of my more modern cameras and I've gotten some fine images with the 124G.

 

[Wayne]

Tell ya what. I've always wanted a Yashi TLR. Since you got it for free, why don't you give it to me. I will pay for the CLA, and all will be well. I will have gained, and you won't have lost, and you'll make another person happy. Win-win!

 

[BrianShaw]

A lot of the decision depends on your ultimate objective. If you want to learn a new skill... have at it. If you want a reliable camera... seriously consider a professional overhaul.

The only free camera I ever received was a Nikon FE that a friend was about to put in the bin. My objective was a reliable backup camera so gladly spent the money on a professional overhaul. In the end, I have had a very reliable camera at about “half the price”.

 

[Kino]

Hi and thanks for the reply!

I see your logic on prices. However, this camera cost me nothing, it was just given to me by a friend having a clear-out, so I don't in this case feel like I would have lost anything by giving it a go. I used to send my Leica's out for professional CLA, but they were considerably more expensive than this! To be honest, if I were going to spend CLA money on it, I would just put that towards a different MF body with interchangeable lenses.

I'm pretty careful and have been restoring vintage hi-fi for years, as well as cars. I know that's not cameras but I've not broken anything yet. As long as I have reasonable instructions and any particular warning points to watch out for, I think I'd be happy to at least give it a go.

Thanks again.

Well if you are bound and determined; start watching videos on YouTube to at least familiarize yourself with tear down techniques. They may not be specific to your problems, but they have to disassemble the camera to reach the same areas, so they are applicable in that sense.

The Master:



Another good channel:



Random:





Invest in a set of JIS screwdrivers; don't use "normal" phillips head screwdrivers UNLESS you grind them down. AGX, this is your cue to jump in...

https://www.amazon.com/Precision-Sc...ocphy=9061285&hvtargid=pla-457224515168&psc=1

Learn how to curse effectively. No links here, but visit your local school playground and listen in; should be instructive.

Good luck.

Oh and one more thing; don't say I didn't' warn you!

 

[lanuitamericaine]

Tell ya what. I've always wanted a Yashi TLR. Since you got it for free, why don't you give it to me. I will pay for the CLA, and all will be well. I will have gained, and you won't have lost, and you'll make another person happy. Win-win!

I like your style - worth a try...

 

[lanuitamericaine]

A lot of the decision depends on your ultimate objective. If you want to learn a new skill... have at it. If you want a reliable camera... seriously consider a professional overhaul.

The only free camera I ever received was a Nikon FE that a friend was about to put in the bin. My objective was a reliable backup camera so gladly spent the money on a professional overhaul. In the end, I have had a very reliable camera at about “half the price”.

If possible, I'd like to begin learning a new skill and have a working camera!

 

[lanuitamericaine]

Well if you are bound and determined; start watching videos on YouTube to at least familiarize yourself with tear down techniques. They may not be specific to your problems, but they have to disassemble the camera to reach the same areas, so they are applicable in that sense.

Thanks! I'd watched the 'How to resurrect' video earlier, but hadn't found the others, and didn't know that Mark Hama was the master of these cameras. In the 'how to resurrect' video, the guy was able to just apply a drip of lighter fluid to free the aperture/shutter mech, but it's different with the dials on the 124G than the levers on his TLR, as there is a slot for access in the lever model. The dials on mine are sealed, so I was assuming I'd have to remove the front cover for access. I found some exploded diagrams, but not an actual repair manual with strip-down procedure, so those other videos should be very useful

I already have a good quality set of precision drivers which I use for electronics work - one thing I was going to ask is I already came across the two-pronged drivers 'lens spanner' I think they might be called? Is there a known good make of these as I'll probably use them in future?

Cursing already a carefully honed skill of mine - ask my wife!

 

[Kino]

I already have a good quality set of precision drivers which I use for electronics work - one thing I was going to ask is I already came across the two-pronged drivers 'lens spanner' I think they might be called? Is there a known good make of these as I'll probably use them in future?

Cursing already a carefully honed skill of mine - ask my wife!

Very good.

Not to belabor the point, but do make sure your precision screwdrivers are JIS standard if you are working on a Japanese camera or you will mangle your cross point screw heads; there is a difference.

Unfortunately, the only available lens spanners I can find are generically made in China of soft steel. Neweer is a brand, but they are all basically the same. Just take care with them, they can destroy your lens and mount in a flash. Chris Serlock, who specializes in Kodak Retina Repairs (https://www.youtube.com/channel/UCBNcopU34d_pGsKTvRzHcsg) has within his videos lectures on how to use a spanner properly, but as far as I know does not have a dedicated tutorial. Basically be extra careful, fit the tips to the slots precisely, just break the ring or fixture loose, remove the tool from the vicinity of the camera and use something else to unscrew the ring/collar or you will slip and destroy something. If you must continue using the tool due to friction, spin the part, not the tool to maintain better control.

 

[ic-racer]

I have had my Yashica 124G since 1975 and the wheels turn very smooth.
I did recently replace the foam rubber around the meter/view screen area.

https://www.photrio.com/forum/threads/yashica-124-g-minor-repairs.176416/

 

[lanuitamericaine]

Very good.

Not to belabor the point, but do make sure your precision screwdrivers are JIS standard if you are working on a Japanese camera or you will mangle your cross point screw heads; there is a difference.

Unfortunately, the only available lens spanners I can find are generically made in China of soft steel. Neweer is a brand, but they are all basically the same. Just take care with them, they can destroy your lens and mount in a flash. Chris Serlock, who specializes in Kodak Retina Repairs (https://www.youtube.com/channel/UCBNcopU34d_pGsKTvRzHcsg) has within his videos lectures on how to use a spanner properly, but as far as I know does not have a dedicated tutorial. Basically be extra careful, fit the tips to the slots precisely, just break the ring or fixture loose, remove the tool from the vicinity of the camera and use something else to unscrew the ring/collar or you will slip and destroy something. If you must continue using the tool due to friction, spin the part, not the tool to maintain better control.

Thanks, I was unaware of the JIS standard, so will order some of those. Yes, I noticed the Neewer brand lens spanners had comments in reviews about questionable soft steel. They did strike me as risky things to put much force on that near a lens surface. Perhaps I should try one of the rubber removal tools first?

I've now watched most of the 'Loose aperture blades' video, which is a nicely detailed strip-down of the front panel, etc., so far. Wow, no wonder those aperture/shutter dials can get stiff - by the looks of it, you have a tiny little wheel (with a poor 1mm wide 'grip') trying to drive some pretty large gears inside, probably all with gummed up old grease! I suppose I'll find out once I get inside where the main stickiness is - if I'm lucky it'll just be on the small gears directly behind the dials themselves.

Is there a standard solvent bath which is good for removing old grease on these types of gears? And is what would be the best grease to reapply afterwards, please?

What I might do is first tackle the light seals and actually run a film through the camera to see if there are further issues than just stiff dials. If the dials are stiff but the shutter speeds are all correct and everything else works, I'll go ahead with the strip-down and lube of just those parts and leave all else alone. If there are more extensive issues, I'll consider options.

Thanks again!

 

[lanuitamericaine]

I have had my Yashica 124G since 1975 and the wheels turn very smooth.
I did recently replace the foam rubber around the meter/view screen area.

https://www.photrio.com/forum/threads/yashica-124-g-minor-repairs.176416/

Thanks, that's great!

Is there a good source of foam light seal material?

 

[campy51]

Go for it. I bet if you put a drop of lighter fluid or use an electronic spray around the shutter button it will free up. The dials should be fairly easy, I have never had to but when you take the front plate off I think you need to have the shutter at 1/500 and the aperture I think fully open or closed and then mark the gears where they are meshed. I would just flush everything with a good electronic spray but just the back of the top plate. That might be all the disassembling you need to do. I don't know about the seals. I think you could have a cla done for under $200 if you wanted to go that route, and you would easily get at least that if you upgrade later.

 

[RMD]

This might be of use :

https://learncamerarepair.com/product.php?product=134

 

[Kino]

Is there a standard solvent bath which is good for removing old grease on these types of gears? And is what would be the best grease to reapply afterwards, please?
!

I use 91% isopropoyl alcohol and naptha to clean surfaces with lots and lots of QTips. If I clean with naptha, I tend to follow with the alcohol to really remove all greasy traces.

As for grease, I use VERY SPARINGY a synthetic grease called "Super Lube", which can be found at many big-box lumber yards and hardware stores.

As for oil, I use simply sewing machine oil; again VERY SPARINGLY and immediately wipe up any stray oil with a cotton bud and alcohol.

Use tiny amounts or you'll wind up with a foggy lens and a frozen leaf shutter from migrating lube when the camera is exposed to high heat.

 

[Kino]

Thanks, that's great!

Is there a good source of foam light seal material?

Try Jon Goodman at Jon_Goodman@yahoo.com

Just email him; he doesn't have an online store, but I have bought over 10 of his refoaming kits and they are very good and inexpensive!

 

[lanuitamericaine]

Go for it. I bet if you put a drop of lighter fluid or use an electronic spray around the shutter button it will free up. The dials should be fairly easy, I have never had to but when you take the front plate off I think you need to have the shutter at 1/500 and the aperture I think fully open or closed and then mark the gears where they are meshed. I would just flush everything with a good electronic spray but just the back of the top plate. That might be all the disassembling you need to do. I don't know about the seals. I think you could have a cla done for under $200 if you wanted to go that route, and you would easily get at least that if you upgrade later.

Thanks. I'm going to remove the front plate once I have the proper driver set and the light seals. It turns out the shutter button is almost freed now, after working the mechanism a bit more (firing it repeatedly) and also it makes a difference if the shutter lock button is too far round, so I think it's probably to do with lubrication around that collar. It also turns out the Aperture dial is not very stiff after working it for a bit. The Shutter speed dial, though, is stiff enough that I have a rather large, long, thin blister on my right thumb from trying to work it a bit! So yeah, that'll have to be cleaned and lubricated at the least.

I'm still surprised by the overall condition seeming very good. Light seals have definitely flattened out and deteriorated, but I think these and the above might be all that needs doing. I'll clean the mirror and screen while I'm removing the top box to get to the light-meter seals, though.

 

[lanuitamericaine]

I use 91% isopropoyl alcohol and naptha to clean surfaces with lots and lots of QTips. If I clean with naptha, I tend to follow with the alcohol to really remove all greasy traces.

As for grease, I use VERY SPARINGY a synthetic grease called "Super Lube", which can be found at many big-box lumber yards and hardware stores.

As for oil, I use simply sewing machine oil; again VERY SPARINGLY and immediately wipe up any stray oil with a cotton bud and alcohol.

Use tiny amounts or you'll wind up with a foggy lens and a frozen leaf shutter from migrating lube when the camera is exposed to high heat.

Is this Loctite Super Lube (the PTFE grease)? I'm in the UK so we have different products here sometimes.

Don't worry, I'll be putting very minimal amounts on, then working it through the gears. I already have a ton of cotton buds for electronics contact/pot cleaning where similar rules apply!

 

[lanuitamericaine]

Try Jon Goodman at Jon_Goodman@yahoo.com

Just email him; he doesn't have an online store, but I have bought over 10 of his refoaming kits and they are very good and inexpensive!

Thank you, will email him.

 

[lanuitamericaine]

This might be of use :

https://learncamerarepair.com/product.php?product=134

Thank you!

 

[Kino]

Is this Loctite Super Lube (the PTFE grease)? I'm in the UK so we have different products here sometimes.

Don't worry, I'll be putting very minimal amounts on, then working it through the gears. I already have a ton of cotton buds for electronics contact/pot cleaning where similar rules apply!

Yes, same stuff.

 

[Kino]

[QUOTE="lanuitamericaine, post: 2379549, member: 94662" Yes, I noticed the Neewer brand lens spanners had comments in reviews about questionable soft steel. They did strike me as risky things to put much force on that near a lens surface. Perhaps I should try one of the rubber removal tools first? /QUOTE]

Sorry, missed this earlier...
IF you can get by with rubber tools, yes, but you will find eventually that you simply cannot get proper access with the rubber tools or they won't fit precisely enough to spin a thin retaining ring and you have to use the spanner.

Get ready to start collecting many, many tools if you embark on camera repairs, even at a casual level. There is always one more you need...