If it's not Sachs @ this point I'd wager you have a Chinese piece... IME, these bits from China never dis-engage, or @ least the few that I got before I realized the Behr units I was getting were made in China and I swapped the all out for Sachs..

Jonathan

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Blue Ridge Mercedes
Jonathan Hodgman
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Enthusiast Service, Restoration & Tuning.
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Specializing in all pre and post merger AMG's including Hammers and DOHC M117 engines.
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