Before the forum went down I posted this thread and got one response that help a lil bit. It is about the fuel gage on my 87 300D.
I replace the fuel sending unit about 3 weeks ago.
When I feel up the tank everything is fine until about half tank left. When the tank reaches about 1/4 sometimes, and I DO MEAN SOMETIMES only when I turn the key to the glow plug position before starting it shows me the right amount of fuel 1/4. Car starts and the fuel indicator needle moves very slowly towards the half tank, after about 10 minutes it shows half tank or just a lil bit below that, and doesn't move. Sometimes it moves, slowly towards the 1/4 mark again. Stop the car after 1 hour or so of driving turn the key to the on position, it shows me half tank. Start the car, it jumps to the 1/4 mark.
Someone here advise me to put 1 gallon of veggie oil in the tank. As a parenthesis it was very funny the way people in the gas station looked at me putting one gallon of pure veggie oil in the tank, since I have no emblems on the trunk indicating a diesel. Anyway... The gage improved a lil bit, it shows more accurate but now it moves very slowly between half tank and 1/4 marks for couple of minutes. I was happy since all day yesterday it showed me 1/4 fuel left. This morning I started the car and BOOM half tank again. I almost punch that gage out of this world, but indeed I didn't have any coffee.
I heard stuff from having algae in the tank, to shorts, to loose grounds or maybe even a defective sending unit. I got the unit from http://www.autopartsworld.com. is it new? rebuild? it was about 60 bucks and the MB dealer ask about 150 for it.
If anyone can help me fix this problem, it would be very much appreciated, and if you are in Sacramento CA, let me know and the beer is on me!
Thanks guys

__________________
1987 300SDL
__________________
Pic of this car:
http://www.gigapipe.net/300SDL/index.htm