Combine beef, veal, and pork in a large bowl. Add the eggs, cheese, parsley, garlic, and salt and pepper to taste. Using your hands, blend ingredients together. Blend bread crumbs into meat mixture. Slowly add water, 1 cup at a time, until the mixture is quite moist. Shape into 2 1/2 to 3-inch balls.
Heat oil in a large sauté pan. When oil is very hot but not smoking, fry meatballs in batches. When the bottom half of the meatball is very brown and slightly crisp, turn and cook top half. Remove from heat and drain on paper towels.
Lower cooked meatballs into simmering marinara sauce and cook for 15 minutes. Serve alone or with pasta.