This one post doesn't make sense to me.
"I pretty much copied exactly what was said in the Manual. I would read the very last pargaraph "note" first as that explains why you are setting the crank at a different degree setting.
The driver is the splined gear on the Fuel Injectin Pump shaft.
From Mercedes Service Manual Engines OM615-617
Set crankshaft to the following values in compression stroke of first cylinder.
615.913 47 Degrees before TDC
615.912 45 degrees before TDC
616 45 Degrees before TDC.
Set injection pump to begin of delivery. For this purpose, keep turning the pump shaft until tooth gap on the driver and the marking on the injection pump are in alignment.
When applying slight pressure on the driver towards the left (opposite to the direction of rotation) the driver will jump back 2 teeth to basic cam circle under the influence of the pressure-loaded camshaft of the camshaft.The 2nd tooth should now be in alignment with the mark on the injection pump housing. Prior to installing the injection pump. Check ounce again whether crankshaft is at 47 degrees before compression TDC of engines 615.913. Or 45 degrees of 615.912 and 616.)
Note: The adjustment of the crankshaft to 47 degrees or 45 degrees before compression TDC is required because the driver has been taken back 2 Teeth. "
http://www.peachparts.com/shopforum/diesel-discussion/276598-w115-240d-injection-pump-re-installation-timing-question.html
The OP in that thread had a problem getting his IP spline to stay line up with the mark on the IP housing. It wanted to spring back a few notches.
Instead of leaving the crank at 24BTDC, I should set it to 45 BTDC to compensate for the spring action of the IP?