mechanical guy called it a coldstart (? item pipe A) and indicated it should go into cap B .. that should right? item C is a now sealed off intermix pipe of some sort, could just be replaced by a straight section of pipe I was told, is this also correct as I remember it.

 

Can't help you with how it actually works but mine was removed and a manual choke fitted....not real sure but have been told they were problematic in the day...someone with far more knowledge than me will chime in I'm sure.

 

You are missing an automatic enrichment device (AED) and its mounting bracket. There are three connections to said device. You should have three pipes going to/from it. they are the fuel inlet pipe, the fuel overflow pipe and the hot air delivery pipe. I think your "a" is the fuel delivery pipe and "b" is the hot air pipe, which leaves "c" as the fuel overflow pipe. If you have a series 2 workshop manual, you will find the illustration in section 19.15.38.

 

been told to plug the A and B links ups. the C pipe I was told is to 'balance' the carburetors? it has been sealed at both sides.

 

Here is a couple of pics with the balance pipe, your carbys look like a different model to mine(maybe HD8) but hose work should be fairly much the same. The two smaller hoses to the outside of the balance pipe go to the crankcase breather at the front of the engine.