In my experience, it is the small hose that is leaking and not the steel pipe. The small hose has to be the factory stuff or it will leak also you should use the factory clamps.

------------------
Benzmac:
ASE CERTIFIED MASTER AUTO TECHNICIAN
LEAD TECHNICIAN FOR 14 BAY FACILITY
MERCEDES SPECIALIST 8 YRS
PARTNER IN MERCEDESSHOP.COM