Hi,
I recently bought a lister d, and in the process of taking it apart to restore and rebuild. First time doing this so learning as I go along.  Something I could do with some help with though is the following… inside the part that you would fill with water, there is a large amount of greenish cotton wool  type stuff. (Photo attached).  I’ve obviously been careful - gloves, mask etc.   Is it asbestos? Or something less sinister? When it’s filled with water, I can’t really see why it would be asbestos? Any help appreciated, there is quite a lot of it stuffed down to the bottom!