Unknown stains on concrete

Giles

I moved into a home that has a lot of different stains on the basment garage floor. The previous owner had no idea what caused them.
Some look like rust stain and it is definately in the shape of a tire thread, about 4x6 inches and there are five. The other stains look like various kinds of paint or stain spills and are different colors.
I have tried paint thinners--Acitone---lacquer--and strong industrial cleaners. I have also tried "lemon juice", amonia and muratic acid with very limited results.
I know this is a difficult question, especially not knowing what caused the stains, but I have tried everything I know. It is not oil stains, I cleaned them.
On all chemicals I tried, I used "scotchbrite pads" and a stainless wire brush.

Just Bill

for rust, try CLR(calcium/lime/rust solution). For paint, try a putty knife and/or paint remover.

Ron6519

Rent a powerwasher and do the floor. Scrape off the globs first.
Ron

Giles

I have used my power washer, there is no surface buildup to scrape. It is in the concrete. I have even tried four different paint removers. I think I will have to clean entire surface and apply a paint coating. Don't really want to do that

Ron6519

You will need a sealer to keep the rust stains from bleeding through the paint.
Ron