Alex,

Take a look at this and see if it fits your situation:

http://tech-meister.com/DieselBenz/TECH/124-series/Pressure-Valve-Seal-Replacement/

If so, Hazet tool 617 589 01 09 00 *might* be the spline tool you need, not 100% sure:

http://www.samstagsales.com/mercedes.htm

There are Japanese alternatives available.

Here are some other links:

http://www.peachparts.com/shopforum/showthread.php?t=128675
http://www.peachparts.com/shopforum/showthread.php?t=83002
http://www.peachparts.com/shopforum/showthread.php?t=128096


Jack