In a skillet cook bacon or salt pork until crisp; drain. Drain clams, reserving liquid; add water to liquid to equal 1-3/4 cups. Cover clams; chill.
In a 3-1/2- or 4-quart crockery cooker combine reserved clam liquid, potatoes, onion, and carrot. Stir in mushroom soup and pepper. Add bacon or salt pork. Cover; cook on low-heat setting for 9 to 11 hours or on high-heat setting for 4 to 5 hours.
If cooker was on low-heat setting, turn to high-heat setting. Stir in clams and evaporated milk. Cover; cook for 1 hour more.