Concrete Stain

[NJ Diver]

I have a few stains in the concrete on my front porch I would like to get rid of. I don't know what made the stain ( I bought the house 1yr ago. House is 4 yrs old).

I've tried a pressure washer w/o any chemicals to no avail. What have you found to be good at removing unknown stains from concrete? If it stops raining soon I'll try to go get some pictures

 

[dankicksass]

If your roof is treated with aluminum roof coat, that can leave staining on your walkway areas beneath, even with a good gutter system. Rain will move some compound to the ground and if waterflow isn't available to move it along, like under a deck rail, the compound will pebble up and produce oily stains. Foot traffic will make the pebbles disappear before anyone notices but the stains stay.

 

[Koken]

Years ago, I used wood bleach to get rid of a stain on a rock fireplace. It worked when nothing else would.

 

[Chloe Taylor]

If your roof is treated with aluminum roof coat, that can leave staining on your walkway areas beneath, even with a good gutter system. Rain will move some compound to the ground and if waterflow isn't available to move it along, like under a deck rail, the compound will pebble up and produce oily stains. Foot traffic will make the pebbles disappear before anyone notices but the stains stay.

Surely would be agreeing as to what ever you wrote, thanks a lot for sharing the information.....

 

[Zeke]

Acid cleaner from the home store will do it, but it will etch the surface making it rougher and prone to more stains.
Or you could go with the flow and stain the porch with concrete stain.

 

[treasureseeker]

Brake Clean

 

[kgorman]

+ 1 on brake kleen, got oil out of pourous flagstone for me

 

[NJ Diver]

I'll give the brake clean a try and let you know.