In addition to simple homemade mixtures, there are quite a few products available for sale that can be used to clean mold from vinyl. PracticalSailor.com tested several cleaners on mildew stains, many of which proved to be very successful at the job.
Vinyl tends to get damaged by repeated exposure to chlorine, so before using a commercial product to clean mold from vinyl, try to clean it with simple, natural solutions. Once mold stains appear, the key is to act fast. Prepare a mixture of mild soap and water. Use the solution to gently rub the areas where mold appears. Since mildew grows in moist environments, wipe the area completely dry after cleaning. If soap and water don't get the stains out, try using a non-chlorine cleaner such as MDR Amazon?s Amazing Cleaner or Star Brite. If the bleach-free products are not successful in removing the mold, try a mild bleach solution. Mix 90 percent water and 10 percent bleach together. With a soft cloth, gently rub the stains until they are removed. Blot the area thoroughly dry when done.
If all other solutions fail, try using one of the other products suggested by PracticalSailor.com. Boat Armor, 3M, Sudbury, Klean-Strip and Spray Nine are all products found to be successful at removing mildew stains from vinyl seat cushions in the tests conducted by the website.