It happened to my 380 engine. Most likely you've bent a valve or two. If the body is worth saving the engine is worth repairing.

The intake, heads and timing cover will have to come off the engine to do the repair. That's if you haven't punctured a piston with a bent valve. I replaced a piston, did a valve job and spent just under a grand on my repair job. I did all the labor except the valve work.

What RPM was the engine doing when the chain jumped?

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84 300SD
85 380SE
83 528e
95 318ic