drive it for 30 miles no problem the park for 1 hour will not restart for 3 hour

Hello, There are many, many issues that may cause this issue, especially for MB vehicles. The issues can range from a key, to a bad engine control module. You really will need to have diagnostics performed, otherwise, you could easily end up replacing part after part. I'll put a link below for certified shops in your area, but let me know if you have other questions. http://repairpal.com/mercedes-benz-within-10-miles-of-silverton-oregon-97381