Dust collection box for AirRam Mk2 (Near Cameron Toll EH16)

I have just replaced the dust collection box on our AirRam Mk2. The old one is still functioning but...
The plastic filter inside the middle of the green foam filter is broken in two parts. I think this component can be separated from the green foam but I haven’t done that. There is fluff/debris inside the centre. Despite my cleaning when I use the AirRam there is a smell I don’t like. Maybe you can get rid of this by better cleaning than I have managed. There is nothing else wrong with this. It collects and retains dust and debris just as it always did. A thorough overhaul after dismantling would probably be a good thing. You don’t need to glue together the two parts of the central filter. It works now but I’m sure it would be possible.