There is a drainplug on the bottom of the tank. Both my Diesels have one, and it is my impression that all MB cars have one.

It is also possible to take out the fuel through where the strainer plugs in. The strainer is a screen-type filter in your tank that is the first line of defense against algae in the tank. If there is algae, you will see it here after the fuel has been flowing to the motor for even a little while.

The strainer is removed with a rather large Allen wrench, or perhaps some clever tool easily fabricated from a bolt head, Do a search on "algae", "tank filter", "tank strainer" and I am sure you will find a lot of useful info.

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Semibodacious Transmogrifications a Specialty

1990 300D 2.5 Turbo sedan 171K (Rudolf)
1985 300D Turbo TD Wagon 219K (Remuda)

"Time flies like and arrow, yet fruit flies like a banana"
---Marx (Groucho)