Well after about 500 km without any issue... I have a leak at the bottom of the steering box :
A few drops of oil ...
I have taken out the steering box and opened it on the bench and didn't see something wrong! the O-rings are new as all the kit joints , So i put some loctite "gasket joint" past around the O-rings and refitted teh box on the car ..... The leak is always here, even after retightening the allen bolts around the bottom cover of the box.
But i don't understand one specific point: there is a spring which actuate a kind of "piston" which moves up and down when you turn the SW . This spring push a "cover cap" on the piston . This cover cap has a very little hole on its side so it can't be leak tight i think this hole is there to evacuate some air when the piston goes up and down .
The piston has two very thin O-rings in its middle. May be those O-rings have been damaged when i have refitted all the parts of the box together?
Someone has an idea about the solution?