Tilley floodlight fuel gauge.

As per the title, how does it work? Mine had a broken glass, so I've taken it off and know it has a float. I presume there's some sort of magnet which causes the needle to turn. Am I right? Any pointers as regards possible fixes/ bodges are welcomed.

 

Have a look at this topic.
It might give you some hints.

 

Great, Carlsson, that's really handy. Thankyou.

 

My pleasure!