Help with 161.025 and loose movement in the case

Hello, I am looking for some help please . .

I have this cal.552 powered '161.025'. No model name on the dial. I bought it a while ago as a potential donor movement, but my wife likes it and would like to wear it instead.

However - the movement is loose in the case and, together with the dial and hands, knocks back and forth and can stop when the rotor catches inside the case I think.

Any idea if there is a gasket or similar that should be there or what a fix may be please?
Any other info about the watch also appreciated.

Thanks in advance.

(photos below)

Agree with Jim. Movement sits in the case back and rests on the lip. Usually a snug, but not tight fit. Your case has a second opening (others don't) which i assume is a way to lift the movement out of the back. Can't see how the movement would move if it's sitting on the lip of the back.

If the rotor is rubbing. The bushing could be worn and it's drooping. Hold by the crown and turn movement face up and see if rotor sags

Does the back and top seal completely all around?

Never owned or restored that style. Beyond the years I purchased, but have had similar older models like it

DON

What's that second slot in the case back?

Hello, thanks so much for the replies.

The caseback and front fit together with a satisfying 'click'.
However, there is obvious movement within the case, side to side and up and down. And I can hear the rotor scraping against something. So it seems that the movement isn't being held securely in the casebook for some reason.

I looked at the rotor as described by @DON, it doesn't look to be sagging.

Any other thoughts?

edit: just to add; when I hold the watch dial down the rotor can spin without scraping.

Again like Jim says. Without it in my hands. Don't know what the problem is

Can't see the side to side movement. Case back is s/s. Movement is brass and would not cause any wear to the case back to widen the placement diameter and s/s back is smooth enough to not alter the diameter of the movement

Only other thing (and this is just my opinion). Pressure over time has forced the edges all around the dial down, so when closed. Not enough downward pressure to hold the movement in place.

Me. While still on the main plate. I would press down on the backside corners of the dial a touch to add that little bit of extra pressure

Take it to a watchmaker and see what the problem is

DON