What were the teeth on the starter gear like when you took it off? Worn?

I'd suspect a bad flywheel gear in that case.

If you bought a rebuilt, it could be bad, too.

I rebuilt starters and alternators at one point in my career. I know they dont do more than basic testing. Gotta keep the productivity up, up, UP!!!

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My first Mercedes Benz. 4/6/07.

1984 190E (201 024) 2.3L four.