Help Needed - Air filter ports, Is there a special hose attachment ? Options

[frostyf]

Hi, my 73 has the following type of air filter on a DJet 2.0L engine.





OD's : A is 13mm; B is 11mm; C is 13mm; and D is a whopping 20mm. The blanked off pipe between B and C is about 14mm.



Is there a special elbow or spigot fitting that connects the hose to the large port (Marked D in the photo). Originally mine had a split water hose here. Looking at Jeff Bowlsby's diagram, its hose run 4 and includes an elbow marked 13 there and what appear to be two spigots - I've marked the connection I think goes between the hose and port D on the air filter with a light green circle in Jeff's diagram.

I've bought some vacuum hose (12mm ID) and the elbow from the parts diagram (914 Vacuum Tube Elbow - New/Replacement R022129637). The hose runs from the Anti-Flash back valve I think to the air filter (that's my take from the diagram). Whilst the hose fits snug on the anti-flash back valve, the elbow or hose have absolutely no chance to stretch over the 20mm port on the air filter (marked D in the photo).

Does anyone else have this air filter? I'm thinking there must be some kind of insert or adapter that fits into the large port on one side, then reduces to say 14mm for the vacuum hose on the other side.

Can anyone shed any light on this or let me know if I've made a mistake interpreting the schematic? Is there a part number for a reducing connector that attaches the vacuum hose to the air filter? This diagram is marked for a 74 2.0L and perhaps I've got the incorrect air filter or diagram? The PET diagrams only seem to show the older round air filter box?

I'd be v grateful if anyone can shed any light on this please; it might stop me going mad!

Thanks - Nick