Carpet is a financial investment. When black marks appear on carpet, it is expensive and time-consuming to shampoo the entire carpet to attempt to remove a stained area. Sometimes, shampooing a carpet stain with a shampooer reaps absolutely no result or it can make a stain worse. Greasy, oil-based stains have different stain-removal methods than water-based stains. The key to removing a black stain successfully from a carpet is to first determine what type of mark it is.
Blot an oil-based stain with a towel, absorbing as much of the oil from the base of the stain as you can. Work the towel from the outside of the stain to the inside as you blot the liquid.
Mix together in a bowl 1/4 tsp of clear hand dishwashing liquid with 1 cup of water. Use a spoon to stir these two ingredients together.
Saturate the washcloth with some of the mixture and dampen the carpet stain with the saturated cloth. Wipe the fibres carefully, working them from the outside in. Be careful not to scrub the carpet.
Rinse the area with clear, warm water by applying water directly to the stain. The carpet should be dampened, not saturated. Place a towel onto the stained area and blot.
Rinse and blot until the hand dishwashing liquid has been removed and until the stain is gone. Use clean towels or washcloths, if needed, until carpet dries. If the stain is resistant and is still apparent on the carpet, reapply the cleaning mixture.
Blot and apply dishwashing liquid as with oil-based stains.
Mix 2 tbsp non-bleaching ammonia with 1 cup of warm water, if the stain is a water-based stain, and not removed by the oil-based removal techniques. Blot the ammonia solution into a cloth, then blotting the stain, working from the outside to the inside of the stain.
Mix 2 cups of water with 1 cup of white vinegar in a bowl, for water-based stains that were treated with ammonia solution. This mixture will neutralise the ammonia solution. Saturate a wash cloth with this mixture, and then blot the stain with the cloth, working the fibres of the stain from the outside in.
For small oil-based stains that are too small for a cloth usage, you can mix the 1/4 tsp of clear hand dish washing liquid and the 1 cup water, and use an eyedropper to drop the mixture onto the small oil stain. Continue with the other steps as described.