I have an assortment of random orangish colored stains on the white vinyl seats in our boat and we have no idea where they came from; they showed up last season when we removed the boat’s “Sunbrella” cover for a launch.
We could see no any indication that something had bleed through the cover and dripped on the seats. At first glance, I thought it was a dark tanning suntan lotion stain that guests may have been using on our previous outing. I have tried “Starbrite Vinyl Cleaner” in the concentrated form, “Soft Scrub”, “Comet”, Chlorine Bleach, and even a chlorinated solvent with no affect. Any thoughts or recommendations on getting the stains out or masking them? It really confuses me because I am particularly dedicated to routine applications of the “ArmorAll” vinyl protective sealant product.
Without actually seeing the boat, I can only guess. I'd bet that the stains are a result of the staples that hold the vinyl fabric to the seat frame corroding. This is less common than it once was, since most boattbuilders now pay attention to these kinds of details. Unfortunately, there are still boat seats being made out there that are upholstered using mild steel staples instead of stainless--or monel, which is best.
At any rate, laquer thinner, used sparingly can often remove the toughest stains on vinyl. Test it on a hidden spot first. Its an old boatyard trick, we are pleased to pass along.
Definitely, laquer thinner is the way to go. - John @ colored wedding dresses info
The other thing that it might be is first how big are the spots? if they are only tiny like the tip of a pen the they are SPIDER POOP and are hard to get off,I have had some on my boat, and I use a spider spray now too keep the buggers away,try the thinner you might get lucky, and use a vinyl product like meguires vinyl treatment , it works at helping keep the staining away.