GP should not get stuck in the OM603 head. How many GP turns but cannot be pulled from the head? A lot of the time it is the carbon deposit ( or the GP got fattened by usage ) on the GP that stops it from coming out. This is what I normally do. I put a 11mm open ended spanner behind the plug. If you have threaded it all out then the spanner should be able to go behind it. Put a big screw driver behind the spanner and turn or use the spanner as a lever. The GP will come out. I doubt there is anything in there that could damage the head. You can also remove the injector and look inside the pre-chamber to see what is blocking the GP hole.

Good luck.

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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.

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