Cleaning exhaust stains from a nylon flag...
Now that I've completed our delivery with our "dress" flag, I want to switch to a normal sized flag for our boat. I have a couple 4x6's that were flown on aCappella but they are all gray-stained from being in proximity of the stern diesel exhaust over a few years.
Through the years, we've tried a variety of cleaners - detergent, Oxyclean, etc. Nothing ever seems to brighten up the flag and take the gray out.
Has anyone ever solved this? I'm not looking for "try this" help - we've experimented with everything. At this point I'm hoping someone has actually done it themselves with success.