If your clock is slow then it is most likely caused by dirt and grease built up and any adjustment will be good only for a limited time until the spring gets weaker again
As mentioned is other replies here, there is a thermo fuse inside this clock. As the clock oil gums up with the grime from decades added as Alfred describes, the movement will sieze. The fuse then "pops".
A thorough cleaning of the movement is essential, hard to find a watchmaker that will take on the task however (I have asked a number of them). I may need to clean it myself, as Markbhai suggests in posting #14 here.
Also, the chrome trim ring will need to be swaged back on after dis-assembly, not all watchmakers can do this well. BTW, the front glass on the clock is plastic (plexiglass?), can anyone suggest a vendor which sells these separate?
/Hans in Sweden
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