420sel Timing Chain Symptoms
 

I have a 90 420sel with 110k miles. My MB mechanic has said to redo the timing chain between 125k & 150k. I am terrified that before I can have done (in about 2-3 weeks) I will have a disaster with mega bucks to rebuild the motor. Can anyone tell me the symptoms of a worn out timing chain, like the noises heard or the way the car drives, idles, etc. Any details you can give would be greatly appreciated. Thanks. Scott

If you've kept up on the oil changes, you are still in the safe zone at that mileage. Usually an extremely stretched chain will rattle when the engine is started. I don't think I'd worry. Then again it's not my car. Just joking.

Peter

PS: Make sure they replace the plastic pieces that hold the oiler tubes in place. A good shop will do that automatically, but it never hurts to remind them.

It seems the 420 engine was more prone to chain problems than other engines. The simplest way to put your mind at rest is to invest in a set of valve cover gaskets and visually inspect the chain and rails. Look cloesly at the left side inner chain rail as it has a tendency to split and or crack along the securing pin bore.

An ounce of prevention.........yadi, yadi