I have a Mosel with the Miyota 8315 and a calendar. I was able to get the original stem out and the new one in with no problem. When the stem is all the way in, it winds, in the middle it changes the day, and all the way out spins the hour hand backwards and does not change the day after going 24+ hours back. I also can not get the stem out after putting it all the way in and pressing the button.
Any suggestions on how to fix this?
Afaik it is normal behavior for 8315 to not change the date by going back in time. It only does it when the time is advanced forward.
Thank you for your reply.
I can’t move the time forward. if I turn the crown one way, the hands spin counter-clockwise, if I turn it the other way, the crown unscrews from the stem.
In that case, you can fix it by adding some loctite to the screw thread and screw in the crown.
Or else just email their support. They will get you a replacement stem and crown.
Thank you for the advice. I am still unable to remove the stem from the movement, do you have any suggestions for that?
Is it because the crown is loose that you can’t remove the stem? If so try to grip the stem thread with the tweezers to remove it.
Another idea is see if the movement is kind of misaligned to the stem hole. That sometimes creates friction that hinders removal.
I’ve only done the Seiko version, but I assume it applies…
There’s a teeny button you have to push on the movement to unlock the stem from the movement. For the button to be visible, the watch must be moving. But even when the button is visible, it’s dang hard to hit. My wife hit it the first time, no issues. I’ve done it at least a dozen times and still I struggle every time.
Point is, this could be weirdly difficult on Miyota as well. Don’t be afraid to re-watch the video and try again, or maybe let someone else have a try.
+1 to CWatch on using loctite. It’s odd that it wasn’t already attached. But loctite is the correct way to do it anyway, so it’s convenient you get the practice 
Do NOT use superglue.