Have an 86 300E with 254000 miles on it. The plugs are fouled out after 3000 miles. It doesn't smoke in the mornings when cranked. Valve seals replaced at 159000 miles and head reworked at 173000 miles. Compression test shows all cylinders at 195-205 range, with very little change adding oil to each cylinder and rechecking. Would replacing the valve stem seals help or is the problem much deeper?

Thanks...

You told us that the plugs are fouled, but you did not tell us what they look like. Are they oil fouled? Does the car consume a lot of oil? What do the plugs look like?

Good luck,

Yes they are oil fouled. I did a search on this subject and found 100s of posts. I figured it would be easier and quicker to ask everyones opinion.
Thanks...

Well, if my math skills are intact, you have put almost another 100k on the motor since the seals were done. You mentioned "head reworked". What did they do?? You could be in the pipeline for at least new seals. If the guides were done, then they may be OK, if not, then it's certainly time for that item as well.