vinyl stain removal

so I uncovered the boat today and there was what looked like urine on the transom hatch. (not sure what it was though) there were no stains on the cover, nor was it wet. Tried cleaning it with simple green, heavy duty vinyl cleaner, a sponge and comet, and a magic eraser (all at different times) nothing worked as a stain is still there. Any suggestions???? I know this has been discussed before, but people always have good ideas here.

Thanks

Most, including myself, have had good luck with letting the sun light kill those types of stains. Leave it outside for a couple of sunny days or just don't worry about it and it will probably be gone after a few outings. For a quicker fix others have had success with soft scrub with bleach used sparingly and kept away from seams because the logic is that too much bleach exposure to the threads weakens them over time.

I used to use copious amounts of softscrub on all of the white vinyl on my dad's boat when I was in high school and had never heard that it could be bad. The interior lasted about 15 years stored outside (1/2 of the time covered, the other 1/2 not covered) without any unexpected degradation or seam failure. That said I've been a little hesitant to use it on my boat since people say it can be bad but my personal experience is that it doesn't seem to affect the life of the vinyl much if any.

supposed to be 100+ the next few days, I'll give it a shot. Thanks for the tips

Mr Clean Magic eraser works really well!

The issue lies within the vinyl characteristics.
Glues and foam backings cross contaminate the vinyl surface setting the conditions for staining to occur.
Additionally the staining can also be mold growth in the foam section that bleeds to the vinyl surface from the backside
Due to the expense many times the foam backing is not treated with antimicrobials.
Lack of a high quality top coat adds to the poor resistance of vinyl reacting to organic compounds that come in contact with it.
If it goes away when exposed to sunlight the condition is Dehydrochlorination.

I would be careful about using any abrasive cleaner as it will degrade whatever protective coating that may be there.

Certain boat brands exhibit this staining problem while many others do not.
Higher quality vinyl’s resist any staining or discoloration.