Thanks much. Like I said, it's been about 25K miles since the valve job. The man who did that work is very respected amongst owners of these older MB cars in this area. He did a compression test then, and said that although the compression was a little low on all five cylinders, some worse than others, it wasn't as low as he'd have expected, given the mileage. He seemed to think the old engine still had a good deal of life left in it at the time. The valve adjustment (naturally) was done at the same time, but I haven't had it done since. I guess it's certainly due. I'm going to give him a call this week, and see if I can get it done. Sure can't hurt....