sailboat rust removal?
 

Bleach and water will quickly remove mildew and mold stains, so probably those remaining stubborn stains in fiberglass and a dacron sail must be rust.

Have tried using Heinz white vinegar and a sponge for removing rust but it does not do much good. Is there a paste cleaner that will cling to the rust and break its' gripe on the white fiberglass or white dacron so's to get into it and bust the rust. Neither fiberglass or dacron are a ferous metal so the rust must just be attached to the surface without too strong a gripe. What works good and cheap on a few different spots on a a nice dacron sail without harming it?

In all my 40+ years of sailing, ..In spite of promises from various products claiming to remove rust, I have NOT found anything to remove Rust from a Dacron sail. Using a bleach will weaken the fabric. You could try Comet Cleanser and a scrub brush, but there will be some rust left at best.

You can try a light compound like 3M Marine Fiberglass Cleaner Wax (#09009) on the hull. This is the "mildest" of three similar products by 3M. If it doesn't remove the rust, it will certainly improve the rest of the hull looks.
In fact I use this stuff to remove scratches from the finish on my near new truck, recieved when driving down a driveway surrounded by rose bushes. It works great.

BTW: Boats that have Stainless Steel pulpits or stern rails that show rust should be cleaned with a Stainless Steel wire brush..NOT an ordinary "Carbon Steel" (magnetic) wire brush. Using a "carbon steel" wire brush will cause the rail to show rust within days afterward.. all over again. Use a SS brush and the job will last. Stainless Steel doesn't Like to be rubbed with Carbon Steel.