Excessive fuel out of rear drain line....Help!

[Markp]

I have been noticing a stronger than usual fuel smell when driving my 68 280SL. Everything is new/rebuilt, there is a consistent trickle of fuel from the small, black vent line that comes from the evaporator in the trunk. The line comes out just behind the rear valance @ the license plate.  Anyone have any initial thoughts?? Thanks, Mark

[Jonny B]

There should be a number of items regarding the fuel smell that you can check with the search function.

There are two small vent holes on either side of the fuel filler neck that vent the tank. These can plug or the lines leading to the vent tank can deteriorate. Do you get a "whooshing" sound when you open the gas tank?  Not sure when this changed. I have an early 250 SL, with the small tank in the right rear fender, which appears to be the same as you indicate. The two small vents go to the little evaporator tank, and then the vent goes to the small funnel shaped vent.

The later cars have a larger evaporator tank in the left rear inner fender, with a line back to the engine.