Mercedes 240D Fuel Tank Removal and Cleaning

My daughters 240D sat for a while and developed a algae problem. I cleaned the tank screen, quite a mess, and installed new inline fuel lines and main fuel filters. I added an algaecide and about 5 gallons of diesel to allow the algaecide to kill the algae. When that happens and algae settles to the bottom of the tank and looks like a layer of old wrinkly vinyl paint. It is not a solid sheet and will be picked up if disturbed. So I decided to take the fuel tank out and clean it with my pressure washer. If that did not clean it enough I would have it steam cleaned.
Of course getting the fuel out will always result in diesel spilling on you no matter what you do. I also had to replace the fuel screen rubber line. Below are the pictures of the job. the hardware and the tank in and out.

  1. Remove the first aid kit and box from hat tray in rear seats. 2 philips head screws. Pull the plastic first aid kit front up and towards the front. disconnect the sender wire and place out of the way.
  2. Drain the fuel tank and plan on getting diesel on yourself.
  3. Remove rubber hose from screen. The screen does not have to be removed at this time. Tape over the screen opening to prevent diesel from dripping in the trunk ( hymm how do I know)
  4. Unbolt the 2 vent lines under the tank on the drivers side of the car, get more diesel on yourself.
  5. Remove the trunk floor carpet and the wheel well plastic inserts
  6. Protect the trunk floor with plastic, Diesel will drip out of the tank. Not alot
  7. Unbolt the forward trunk wall. 4 bolts 2 on the rear seat hat tray and 2 on the floor.
  8. Remove the vacuum reservior. 1 push pin assembly at the rear on the rear seat hat tray. Disconnect the vacuum line and move to the side.
  9. Unbolt the 4 fuel tank mounting nuts, remember the large washers are on the top.
  10. Remove the tank by moving the driverside towards the rear first and sliding the filler neck out of the body opening. spill more diesel on yourself or the trunk.
  11. Remove the fuel screen and sending unit.
  12. Clean with a high pressure washer or take it to a radiator shop to clean it.
  13. I attached my shopvac hose to the filler neck and duct taped it tight. then I turned it on blow and allowed the tank to dry this way for 4 hours. Make sure the vent lines are empty of water. This may require rotating and moving the tank to get the lines to drain. I used a flashlight to see into the tank and it looked quite clean.
  14. Before reinstalling the tank, blow out the supply and return line and change the filters.
  15. Use an algaecide every 6 months.
  16. OK you had an algae problem and had to do all this work. Since your there consider the following. Clean the screeen completely, I used brake cleaner in a can. Replace all the rubber lines you had to disconnect. You may have to reglue the bottom rubber cushions on the tank back on, use 3m weatherstrip adhesive. Open and clean the sending unit. If the tank had a algae problem so does your sending unit. Again brake cleaner spray. New screen and sender Orings. New filler rubber bushing if your is worn. Check your vaccum reservior, If cracked or leaking repair with epoxy. Check the vacuum line to reservior connector. Seal or replace if its bad. Your under the rear of the car so check everything. I treat the axel boots with 303 preservative while I'm under there, be careful not to break the boots if they are old. Again if you are doing this consider using an algaecide every 6 months or so.

The first picture shows the mounting bolts for the trunk wall panel ( this shows the lower one).
There are 4 bolts total... 2 under the hat tray of the rear seat (accessed from the trunk side), and 2 on the floor of the trunk.
Access for all 4 bolts is in the trunk.

image


Passenger side upper trunk wall bolt and vacuum tank
image


Passenger side tank area. Filler neck and vacuum tank
image


Left side
image


Left side, tank removed
image


Right side, tank removed
image


This is is what the water looked like that was drained out of the tank while high pressure washing the tank.
image


Have a nice day!
And if anyone knows how to get the diesel smell out of my shop clothes, without a match, let me know.
3 washings and they still smell.

Mercedes news, Mercedes reviews, Mercedes DIY...