I just bought the Brinkman,
Since a Rotisserie is an optional item for your model grill. I assume you have purchased one that is approved to be used on your model Brinkmann Grill Smoker. If not, I recommend that you Do Not use it. If it was approved, read and follow the directions that came with it regarding installation, setup and preparing to use the rotisserie.
The Rotisserie can only be used when you are not grilling anything else on the grill. Remove the grill grates directly in front of the rear infrared Rotisserie Burner. If you Don't, they will be in the way. In their place, you are going to use an aluminum pan (like a pie pan), as a drip pan for whatever you're cooking on the Rotisserie.Place that on top of the burner's flame tamers. Make sure the rotisserie motor is in place and you have electric power to it. Test the rotisserie spit, by inserting it into the motor's spit holder. If you have a Counter Balance, attach that near handle on the spit shaft just below the handle. If your rotisserie is missing the counter balance, you can not use the rotisserie.
Remove the rotisserie spit and place whatever you're planning to cook on it, following the directions that came with rotisserie kit. Make sure the spit forks are tightly embedded in the meat, whole chicken, etc. If a whole chicken, tie the legs together like a Thanksgiving Turkey around the spit..
Light the Rotisserie Burner and close the hood of the grill. Allow the temperature to reach a minimum of 250 degrees F, before opening the hood and installing the food loaded rotisserie spit.
Be careful, as the interior of the grill will be hot. Install the spit as you did earlier. Make sure it fits into both sides of the grill's hood correctly.
Turn the Rotisserie Motor ON and watch as the food turns. If it turns and then sort of bumps, when the spit turns around, adjust the counter balance to stop this. It should turn smoothly. Once all tha is completed, close the hood and allow the food to cook for whatever time, you would cook it in a kitchen oven. Rotisserie cooking is like smoking food. It's a low (temp) and slow (time) process. But, the flavor rewards are GREAT. Only check the food occasionally. The more you open the hood to peek, the longer it will take to cook. Each time you peek, add 10 minutes to the cooking time.
All of this, was sort of a thumbnail sketch of rotissering food. Search the web for recipes and techniques. You'll be amazed at what's out there.
Hope this helped you. Please let me know and Happy Grilling!!