2000 E320 cdi estate starts then stops!

[nicholash]

Hi all, I have just inherited a 2000 E320 cdi Elegance estate. The car has been off the road for five years following a minor nearside front accident that caused a small amount of damage to the lower wishbone. This has been replaced. Overall the car is in very good shape considering how long it has been standing still. The main issue that I have is that the engine starts, runs for around a minute then instantly cuts out!. The injectors have all been removed, cleaned and the seats reground. All engine bay fuel lines have been replaced and new o rings fitted. The high pressure fuel pump has been replaced with a reconditioned unit. The fuel filter has been changed with a genuine MB unit. all this was done to no avail! I then occured to me that there might be a blockage somewhere in the fuel lines. After undoing the union to the fuel rail and cranking the engine it was clear that there was plenty of fuel delivery. Next I disconnected the bleed off return hose that sends unused fuel back to the tank. I put the end of the hose into a fuel can and got my brother to start the engine. Bingo! The engine ran perfectly and revved freely with fuel running into the can from the bleed off return pipe. This seems to have proved that there must be a blockage in the pipe returning fuel to the tank. I have checked the fuel cooler under the car which was in good condition. Having disconnected the hoses from the cooler I tried to blow through the return pipe to the tank but couldn"t. Does anyone know if you should be able to blow back into the tank or is there some sort of valve along the line. I feel that I am nearly there with this problem but would really be grateful if anyone has any suggestions. Nick.