Saute bacon. In a large pot, add celery, onions and cook until tender. Add 3 cups water, 1/2 cup clam juice, tomatoes, potatoes, carrots and add salt, pepper and thyme. Cover, simmer 35 minutes.
Blend 2 tablespoons flour with 2 tablespoons cold water. Stir and cook to boiling. Add 2 to 3 cans of clams; heat 5 minutes more. Serves 6 to 8.