Preheat the grill to 400 degrees.
Bring a pot of salted water to a boil on high heat.
Drop potatoes into boiling water. Cook for 8-10 minutes, or until a fork can go through easily. Then, drain and let coolslightly.
Place corn, potatoes, onions, and shrimp in alarge mixing bowl. Toss with olive oil, old bay seasoning, salt, and pepper.
Add andouille sausage slices and clams, mix to combine.
Tear 4 large pieces of heavy duty foil (at least10x10 inches). Place seafood mixture in the center of each piece of foil.
Add ½ tablespoon of butter to each foil packet.
Then, pinch together sides of the foil until itis sealed.
Place packets on the grill and cook for 10 minutes with the hood closed.
Serve with lemon wedges on the side!