Cap on swan cap on 350i

[DIB350]

Can anyone advise me where the filler cap on the swan neck comes from...mineis leaking slightly when the engine is up to temp and pressure. I'm going to replace it. I think I might have some airlocks since topping up a while back.

[TA14]

It's a generic one so any motor factors should have one.

[DIB350]

Nice one, will get one ordered.