Thanks, Pooka..
I have changed the fuel filter at the injection pump a couple of times-I know that there is a fuel system problem because the filter has been dirty each time. As far as the tank goes it looks good from the outside-the original coating is still there although not knowing the PO's to any extent I may have a newer tank or a good used one. I am taking it off to be sure that it is clean. I will take Todd's advice and run a piece of wire thru all the fuel lines to clean them.I will carefully inspect the flower pot and carefully run a wire or maybe a gun cleaning rod to check the feed and return lines in the tank. Once I have flushed everything and I am satisfied that it's all clean then I will put the whole system back together again.
I also intend to replace the rubber hose between the injection pump and the filter as well as the injection pump return hose. I will then change the filter again, bleed the lines and see if I can get the engine to stay alive longer than it has up to now.
If I find any gross violations of the tank I will look for another tank on the MB parts circuit....
By the way when I was draining the tank there was quite alot of frog eyes as we call them in the trade and stuff which just shouldn't be in a gas tank..
Thanks again