The tech would have rather done a new motor if it was an option. They were backed up 3 weeks before getting to it. took 2 weeks to get done.
A big prime rib will continue to cook after you take it out of the oven, so for a final medium-rare temperature of 130 F you need to take it when it reads 120 F on your instant-read thermometer. Note that the U.S. Department of Agriculture recommends all beef cuts be cooked to an internal temperature of 145 F.
1 Preheat the oven to 200 degrees Fahrenheit (93 degrees Celsius). Cook 6 to 8 hours. 2  Preheat the oven to 225 degrees Fahrenheit (107 degrees Celsius). Cook the ribs for 5 to 6 hours.  Preheat the oven to 325 degrees Fahrenheit (162 degrees Celsius). Cook the ribs for 3 to 4 hours.