I ssume you have vinyl cusions. Try 'SoftScrub with Bleach'. Test it in an inconspicuous spot first. Rinse well with a sponge and towel dry completely before storage. If the mildew is extensive, the Clorox mentioned will probably get the mildew but it can be tough on stitching, especially if not completely rinsed out.
Other types of bathroom tile mildew removers will also work but you have to avoid the abrassive ones.
i heard from a boat broker of a boat i was considering that had cracked vinyl bolster pads that certain cleaner chemicals will greatly acclerate its aging and deterioration. The boat was a 2004, but pads looked 10+ years old and it was a northern boat (not S.Florida).
i couldn't remember the chemical(s).
anyone know which ones to stay away from for vinyl? :roll:
I think he means the cabin cushions.
Without removing the covers and doing as gw204 suggested, the only thing I can think of is a foaming type of carpet cleaner. Spray it on, scrub, let dry and vacuum off.
After I clean the cushions, I apply 303 Aerospace protectorant. This works for vinyl exposed to sunlight as it helps block UV rays. I don't know if it will help inside the cabin. That said, I would expect that any auto vinyl interior type of cream or polish would help prevent premature drying out.