It is CW if you are facing the engine. You can tell also by spinning the engine using the starter motor - tie down the shut off valve if you do NOT want the engine to start.

You can turn the engine whichever way you want, it is not going to jump a teeth on the OM603. It is physically impossible for the timing chain to jump a teeth if turned backwards ( CCW ) as the TC is restricted in 2 places, near the IP and the oil chain.

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Not MBZ nor A/C trained professional but a die-hard DIY and green engineer. Use the info at your own peril. Picked up 2 Infractions because of disagreements. NOW reversed.

W124 Keyless remote, PM for details. http://www.peachparts.com/shopforum/mercedes-used-parts-sale-wanted/334620-fs-w124-chasis-keyless-remote-%2450-shipped.html

1 X 2006 CDI
1 x 87 300SDL
1 x 87 300D
1 x 87 300TDT wagon
1 x 83 300D
1 x 84 190D ( 5 sp ) - All R134 converted + keyless entry.