Mamiya 6 - Shutter release button not clicking, film advancing endlessly

[adifrank]

I have a Mamiya-6. A couple of days ago it was working fine. Today I put in a new roll of film, closed the back cover and started to advance the film with the film advance lever. But noticed two strange things: [1] The shutter button would not function, I would press it, but nothing happens [2] The film never stopped. I could advance the film with the film-advance lever endlessly (without having to press the shutter button, which as mentioned, would not function).
So I removed the roll of film to try and figure out what is wrong. Strangely, When the back cover is open - the shutter button WORKS! It clicks! But then when closing the back cover again - it stops working. I press it and no click. And I can pull on the film-advance lever over and over.
Any ideas what might be wrong?
I'm very worried, because as I know Mamiya stopped making new film advance mechanisms for the Mamiya 6 and because of this it's almost impossible to fix one these days...
It might be just a simple problem that I'm overlooking. I'd really appreciate help with this. Thanks! 

[theguywitha645d]

Check the batteries and check the lens is cocked--you can cock the lens by taking it off the camera. And the lens is locking when you pull it out?

I think it may be the winding mechanism, but those are the only things I can think of.

[adifrank]

I'm not sure how to check if the batteries are okay, but (a) the light meter works and (b) the shutter release button DOES CLICK when I press it while the back of the camera is open. It's only when I close the back of the camera that the shutter release button won't click.

I also tried another role of film. But I ran into the same problem. I can advance the film with the film-advance lever until the film completely goes to the other side without ever clicking the shutter release button. AND even if I DO press the shutter release button - it won't click.

[adifrank]

This is what I've tried and found out so far...

When the back cover is open, the shutter release button fires normally. When the back cover of the camera is closed, the shutter release button will not fire and a red warning LED lights up in the upper right-hand corner of the view finder. I found a tiny pushable pin in the bottom crease where the back cover goes in when closed. While the cover was open I pressed the pushable pin with the tip of a pencil and the camera was fooled to thinking the back cover was closed - so the shutter release button fired fine (with LED warning light).

According to the Mamiya 6 manual - this warning LED lights up when pressing the shutter release button in the following cases:
a. when the lens mount is retracted
b. when light shield curtain is closed
c. film is not loaded
d. shutter has not been cocked (film advance lever has not been wound until it stops)

I tried cleaning the gold circuit connectors on both the lens and the lens mount. That didn't help.

I currently put in my 3rd test roll of film - and with the film in the camera the shutter release button still won't fire and the warning LED lights up just as it did without film in the camera.

There's a small hidden button on the right side of the camera which I never new about. According to the manual it's called an Emergency Winding-Stop Release Button. I read the description, but couldn't quite understand what its function is. Could this button possibly help me or be connected with my problem? Can someone explain exactly what it does? Here's the text from the manual:

If the batteries have been depleted - especially when the power on-off lever has been set to the OFF position during long exposures (at "B" ; 4 seconds or 2 seconds) - the winding-stop prevents the film from being wound. If this happens, push the emergency advance/stop release button with a pen or other pointed object as shown above. The advance/stop is then released, allowing the film to be wound. Please note that that  articular frame will be poorly exposed. The emergency winding-stop release button should not be used for any other purposes.

Please help... I'm in the middle of a photography residency program in New York and I am lost without my favorite camera. 

Thanks

[theguywitha645d]

I wonder if it is that button. First, is there a repair service you can contact. I would also get in touch with Mamiya and see if they have an idea. You are probably going to have to wait until Monday. I have had two Mamiya 6s and this is the first time I have run across this.

Push come to shove, can you buy another body? Either on eBay or at a place like KEH.com.

[adifrank]

I wonder if it is that button. First, is there a repair service you can contact. I would also get in touch with Mamiya and see if they have an idea. You are probably going to have to wait until Monday.

I will call MAC Group on Monday.

I have had two Mamiya 6s and this is the first time I have run across this.

Do you mean the first time you've heard about this sort of problem? Or first time running across that button?

Do you understand what Emergency Winding-Stop Release button does?
I wasn't able to figure it out from the explanation in the manual.

[theguywitha645d]

It is the first time I heard of your problem. The button appears to allow you to get a roll of film out of the camera when a battery gives out and this can happen during long exposures. I have taken 5 minute exposure in the cold where the battery died preventing the camera from advancing. I took the lens off and manually rechecked the shutter to solve that--I actually did not know the button existed and I have owned my Mamiya 6 since 1991. I recently sold my other 6 MF. In all those years I have never known the camera to simply allow the film to be wound through it. Perhaps the button is stuck or some internal corrosion has set it--all of this is speculation.

Good luck. I know how attached you can become of the best medium-format camera ever made...

[adifrank]

Hi. I spoke to technical support at MAC Group in New York. They wouldn't let me speak to a technician to try and troubleshoot the problem on the phone. So without a choice I'll need to have the camera sent for repair.

But I believe I have managed to narrow down the problem.

After doing all sorts of tests, I have a strong feeling that the problem is that for some reason the camera is not registering there is film in it. And that is why the shutter release button won't fire, the film-advance lever will wind the film without it stopping at frame 1.

Does anyone know how the Mamiya 6 detects if there is film in it? Is there some sort of lever or electronic censor?
If I find out what detects the film, I might be able to figure out what the problem is.

Thanks!

[theguywitha645d]

The roller just passed the film gate before the take-up spool detects the film. It is driven by friction. I can't remember if the design is the same for the 6 and 6MF, but I remember one having rubber at the top and bottom of the roller.

[adifrank]

Yes, I see a roller in the place you describe. I currently have a roll of film in the camera for testing so I can't really have a good look at this roller.

But what really confuses me is that the film frame counter works!
As I wind the film, the frame numbers in the counter advance as well. So it really looks as though the camera DOES in fact know it has film inside. Really weird...