Originally Posted by barry12345

Sounds like head gasket or turbo seals. There is a potential problematic oil feed to the head just ahead of the number one cylinder on the 603 blocks. Gasket failure can feed oil into the first cylinder.

Just remove the connector to the turbo to see if it is the turbo seal. Strange it will not start though.

Also removal of the number one glow plug. To see if the cylinder is spitting oil out. Tie down the injection pump shutoff first of course. I do not think the bent rod syndrome just starts up out of the blue like you experienced. It takes time and wear to allow the oil to get past the piston. Nothing Is written in stone. The not starting leads me to suspect the chain may have jumped timing over the other choices. Easy to check on these engines.

As for the rod bending issue. Mercedes never released the cause officially. To the best of my knowledge. Perhaps for liability reasons. The block is substantially weaker than the 3 liter block. Was obvious on examination. I still feel that plays into it. Why some fail and others may not. Could be as simple as the block casings quality varied a lot. Take your pick of theories. If I had one I would not idle it a lot.

Yet as they say. Opinions are like rectums. Everyone has one.

It is also not too late to start your own thread. That will produce far more help than I can give with my limited experience. This is probably the best support site for these older Mercedes diesel cars.