Thread: O-ring size STC4509? another question

Have a leaking fuel pipe on our Td5 where it enters the head.
It's happened before when the connector got loose.
I want to replace the o-ring STC4509 and hoping to get a size from someone so I can pick up on the way to recovering the car.

Thanks


Assuming it is the loose pipe going into the head from the FPR - how tight should this be, it's a pain to get at.
Can you use some sort of sealant or thread lock?

Didn't find this on the first search but now...

Found this 6.0 x 1.5 mm Viton 75, (6x1.5V7),

Great resource as always.