dow key loose connector

[K8DI]

I have a dow-key relay type 60-G-SC2, the fairly typical T shape with the common connector on the end and the two NC/NO connectors out the sides. Got it off ebay, seems likely to be new, there was no trace of solder on the turrets on the coil, in fact they needed some cleaning and a bunch of heat/flux to take solder. When I put on the cable on the common connector, and tightened it firmly, that connector gave a little. When I removed the cable, it gave a bit more. It is loose. It seems like there may be a set screw or a pin in the side, but nothing I have fits it (0.050", 1/16=0.062, 1.5mm=0.059, 2mm-0.078 hex wrenches).

Questions --

1) is it a set screw? what on earth size would it be?

2) how much movement does it take to ruin it?

3) what if I put a drop of locktite on it? Will it insulate the connector from the body?

4) is there some way to open it for inspection to see where it is supposed to be (vs. twisted/straining internal parts)?

5) any other way to tighten it?

[W1ITT]

It's difficult to see from the photo but, perchance, does it want a Bristol Spline wrench?  Those were very much in style in years back.
They are available on Ebay and elsewhere.
73 de Norm W1ITT

[Pete, WA2CWA]

hardware/mechanical spec sheet:
https://web.archive.org/web/20031011055212/http://www2.dowkey.com/pdf/60a.pdf

It looks like a Bristol spline. Spec sheet doesn't identify what it is.

[K8DI]

Thanks, gents!

It's hard to get a decent photo of a tiny black recess, but the attached seems to show a 4-spline socket. I'll try the local club, there's a Collins guy (former employee) locally who almost certainly has the right size wrench.

Any comments on the rest of the questions I asked?

[KC2ZFA]

this is what the flapper looks like...so if the connector rotated then you're not getting the correct contact action. Opposite the input there should be a removable plug that gives you access to the contact points. Check alignment, clean them, etc.

Peter