@NormNormalMan I'm going to a Mercedes dealer today to see if I can get a replacement hose. I have a leak from the fuel pump to the filter. The original hose failed. It looks like there is a liner inside of these hoses and the one inside of mine has collapsed and is blocking fuel flow. This may be the case with yours. I tried regular 5/16" fuel line and it started leaking worse. It may be caused by the cheap screw clamps I was using. I've ordered new clamps that should be here on Sunday.
I'll report back with any information.


Liner in fuel line collapsed.

I tried to substitute 5/16" fuel line from a parts store and used screw clamps which are garbage.