One piece seal vs rope seal

[Harold Degand]

Hello.

I’ve a problem with an one piece seal on my french flatty.

I choose this seal to avoid oil leak.

Of course, I put a sleeve over the helicoidal groove and silicon everywhere it should be.
My pulley isn’t like an 8ba, the groove is machined in it.

Unfortunatly, I have a leak.

So, I wonder put some rope seal.

Did someone have the same problem ?

Thanks for your help