Hi again, At least one possible variable is okay. JT 20 is right all the rocker arms should be removed if the cam has to be turned quite a distance. Each rocker must be marked for its actual location on your engine as well. They wear in to specific locations.

The washers orientation if it has affected the timing marks positioning might mean very little movement is required. If that was so you might be able to leave the rocker arms on. This is highly unlikely though. You might establish this be peeking as further described.

You could try to see if the cam can be moved the required amount with no interference. Yet the valves/pistons should present interference if there is much movement required.

As for the washer etc. You are on the scene and it should be obvious what assembly methology is going to be correct from your cam lobes general positioning. With those rockers off you may have been able to bunch move the chain over the sprocket. With the tensioner removed a tooth or two at a time.

If it is determined the washer requires reorientation the chain sprocket will have to be removed. You could slide the sprocket ahead a little first and examine the relationship of the keyway to the mark on the washer.

Of course if the mark is directly above the keyway the orientation of the washer does not matter. At this point I think you have worked around this area enough to be in control. One last item though. Just out of curiosity where is the camshaft mark at present compared to where it should be?

I believe all the confusion for you has ended as well or hope it has. If you are still working long hours take a minute to think things over as you go along. Keep us informed and again anyone should chime in that is able to present a better methology. I certainly do not know it all.

I used to hang the timing chain from something overhead on the old mercedes gas engines. I do not know if this is really required on their diesels. Even a shock cord or wire as suggested by JT 20 will not hurt anything though.

If you are still uncertain of anything at all post it. There are many on site with lots of experience. They like to help out when possible. You will be able to help others out with simular problems as well after this.