My SL is an '85 with 188K miles on it. I double checked the invoice and it sayed the tensioner was also changed with the chain. It does have the double row chain.

It did occur when trying to start the car. Wife said it did make a funny noise when it happened. Guess I was fortunate that it didn't start. I was concerned about piston/valve interference because of it not starting. I'm now thinking that the friction of the chain on the valve cover wasn't letting it spin fast enough to start. The inside of the cover is very gouged.