[From Ohio Valley Natural Fibers, via the Internet Archive]
Using a top load automatic washer, turn off the cold water line and place 5 to 6 lbs of raw fleece in the washer. The hot water coming into the washer should be at least 120oF and preferably 140o. Check it with a candy thermometer. Use your normal non-chlorine laundry detergent. The best we have found is ERA. [Personally, I use Orvus Paste, an animal “shampoo” available at many farm supply stores, and Dawn dishwashing liquid to get rid of the grease.] If the fleece is very greasy or it is Mohair, add 3-4oz of denatured alcohol. Put the detergent on the fleece and fill the washer with hot water.
DO NOT AGITATE
Put a rubber glove on your hand or use a stick so you can gently work the detergent into the fleece. Let stand for 10-15 minutes and then spin it out. Fill with plain hot water as a rinse.
DO NOT AGITATE
Gently move the fleece, let stand a few minutes and then spin out. Do this all again, wash and rinse twice. Then put the fleece on a screen to dry. Extremely greasy fleeces may have to be done again. [I generally go through two wash and rinse cycles, with an extra rinse at the end if the rinse water still shows dirt. Hint: Don’t panic at your first wash water as it drains. Mine often looks like chocolate milk.]
With much gratitude from:
Ohio Valley Natural Fibers