Mamiya RZ Pro II shutter problem

[brent.bousquet]

My rz has developed a problem where the shutter wont properly fire. The mirror will go up and the shutter will close but then get stuck shut and not re open to let light through. I tried two different lenses to rule that out. Also I took the front plastic cover off the lens mount and found if I apply even a little pressure to the gear at the bottom it will fire the rest of the way. Does something need to be greased or is a spring worn out? any help would be appreciated.

 

[MattKing]

How is the battery?

 

[brent.bousquet]

brand new I just replaced it. I also tested it with a Sekor c 180 which is an RB lens so it has no electronics and it did the same thing.

 

[EdSawyer]

Not sure, but sounds like a mechanical issue. I have the repair manuals posted here: http://www.edsawyer.com/lenstests/

Good luck,
-Ed

 

[brent.bousquet]

Not sure, but sounds like a mechanical issue. I have the repair manuals posted here: http://www.edsawyer.com/lenstests/

Good luck,
-Ed

thanks this will help a bunch. Unrelated but the previous owner broke the ribbon cable gong out to the lens mount so I just used the rb lenses I had but if I put it in the same rbl mode could I still use the rz lenses just manually?

 

[EdSawyer]

Likely so, they should fire at the fixed 1/400 speed regardless. It sounds like a different body altogether might be the easiest solution to both issues.

 

[flavio81]

My rz has developed a problem where the shutter wont properly fire. The mirror will go up and the shutter will close but then get stuck shut and not re open to let light through. I tried two different lenses to rule that out. Also I took the front plastic cover off the lens mount and found if I apply even a little pressure to the gear at the bottom it will fire the rest of the way. Does something need to be greased or is a spring worn out? any help would be appreciated.

That is the gear that moves the device that cocks and fires the lens shutter.

This means that part is stuck (lack of lubrication / dirt, or it has gotten stuck because of misalignment, screws coming loose, etc).

Or, the rest of the cams and gears that move that sprocket require lubrication. This is a rather easy job on the RB67; don't know about doing it on the RZ which has electronic circutry.

 

[brent.bousquet]

I enjoy tinkering and dont really have the money for a working body, which is why I got a broken one and the RB lenses have proven good enough. Im just waiting until another broken one shows up on ebay with a different problem.

I lubed the gears and the problem still persists. Its almost like when the shutter is cocked the camera doesn't have enough spring power to fully fire the shutter. Is there any way to tighten the spring which I think is called the drive spring based on the repair manual? I also have an RZ pro body to steal mechanical parts from unfortunately they are different electronically.

 

[brent.bousquet]

is it possible that the lenses are causing the problem? The camera seems to work fine with no lens attached and the lenses fire every time when not attached but is it possible that the force required to fully fire the shutter is just a bit too much for the camera but unnoticeable firing them by hand?

 

[flavio81]

is it possible that the lenses are causing the problem? The camera seems to work fine with no lens attached and the lenses fire every time when not attached but is it possible that the force required to fully fire the shutter is just a bit too much for the camera but unnoticeable firing them by hand?

The force to require to fire the shutter is minimal and you can confirm this by grabbing a RB lens and triggering it (you need to press on the pin that 'frees' the two protruding pins, and -while holding this pin- twist the two protruding pins counterclockwise).

I would not mess with ANY spring until inspecting the camera and making sure every involved mechanism is clear and lubricated.

Finally on the RB the circular plate that engages with these pins in the camera rotates on tiny ball bearings. It is unlikely, but perhaps some very very rough handling have made this plate got loose and thus the ball bearings have fallen down. This would make the mechanism experience a lot of friction.

 

[brent.bousquet]

The shutters fire fine when I have them off the camera and I completely lubed the mechanics in the camera this weekend and it made no difference. It's frustrating because it seems to be completely random the shutter will fire fully once then the next time it just won't then it will fire 10 times in a row then it won't.

On the plus side I am very familiar with the internals of the camera now and found an issue with the wiring which I was able to fix.

 

[brent.bousquet]

So I have ruled a few things out but the problem isnt fixed. I know it definitely isnt the lenses, lens mount bearings, main drive gears, or main spring. I took it to a guy who fixes mechanical cameras and he told me to throw it away haha so I guess this is just how the camera is now.

 

[Edenortega]

Hi @brent.bousquet is this problem fixed? Have the same going on now