There are 2 skinny little black pipes run from the radiator up over the engine block. One has a connector right next to where it passes where the part load breather tube enters the engine cover. I am losing coolant from that connector in the skinny pipe. I hope my description is adequate.

Can I fix a leak in the connector myself ? Some kind of sealant I cant apply that will fix it, or do I have to buy new pipe and get it fitted ? Im hoping someone can recommend something :-) Thanks in advance.

 

I'd buy a new pipe. The plastic gets brittle over time and should be replaced.