Well, fellas, this is the reason my 500SEL is down. They are plastic and when they break the timing chain loses tension. With loss of tension the timing chain can screw up the timing and what happens?......BENT VALVES!!!!
Rassin-frassin, fricken-fracken. This is what happened to my 500SEL. Now it will cost me about $4000 to fix unless I do it myself with help from mechanic buddies.