Thank you, Oedipus, the information you gave here was much appreciated, since I was still unsure what model I had, after reading "The His Master's Gramophone" book concerning these two models. From your description I now understand I have Model 251, I also upload a photo of the motorboard and turntable of this gramophone, since this is not found in the same book. I bought this gramophone one year ago, it was for sale for a longer period, but no one seemed to want it, despite that it remains in very good condition. It actually also plays very well, and I love the purple felt too, and also the lovely smell it has when opening the lid. I have absolutely no clue where this smell comes from, but I like it a lot, for me it is the HMV smell.
I should maybe be hesitant to service the motor though, since it easily may remove the smell.
This is kind of an interesting topic too really, at least to me, the smell inside old HMV floor models. I have three of them in my house, and they all have this particular and to me interesting smell under the lid cover. Does someone know where this smell is originating from? Even after all these years, the smell is still as strong as when I got my first floor model 30 years ago. Have someone else paid notice to this? Is it the woodwork, or?