Over the weekend I helped a friend replace the timing belt, tensioner, water pump, thermostat and belts on his 1989 240. All went fairly well. We both enjoyed the work and looked forward to the satisfaction of having done quality work ourselves and saving a few bucks. When the job was done, the car fired right up and my friend drove home without incident.

The next morning, the car wouldn't start! He had his mechanic look at it and it turns out we neglected a very important last step that was right there in the Bentley manual. After installing the new belt, we had forgotten to manually "turn the engine over(clockwise)one full rotation" to make sure that the entire belt received proper, even tensioning. Neglecting this step caused the rotating sprockets to eat up a couple of teeth on the belt and the belt to slip, throwing off the timing and causing the no start.

In the end my friend is out the cost of a couple of hours of labor and a new belt, but we both learned valuable lessons. I learned to read and follow all directions carefully, and he learned not to trust a friend who thinks he knows what he's doing!
Todd