[user1007]

If you are right in your assumptions? Oil based things, with exceptions, cannot stick to water based---usually acrylic underneath.

There is another possibility here though. Someone may have sprayed the last layer with something like Thompson's Water Seal which has wax in it.

Good news? If the top layer is all coming up?

Powerwash it and see what you have with that peeling layer out of the way.

 

[ChaoticBliss]

Well what happened was the first coat was already about half peeled up when the second oil based coat was applied. The concrete actually has two different colors now, dark where the oil based is and light where the water base is. The second coat was done professionally so I don't think it is something like Thompsons. Power washing has been tried and only removed any loose sealant.

 

[jomama45]

I'd be careful with the power washer, as too much pressure concentrated in one spot too long can and will do damage to the surface.

Here's a "stripper" I've used before to remove some water-based. There are others out there as well, but you'll need to get them from a concrete supply house. My experience with the stripper is that it doesn't go very fast and still takes a lot of effort to get the sealer off.

http://www.wrmeadows.com/wrm00170.htm


When you get to re-sealing it, I'd suggest on only using a solvent based sealer, less chance of running into this problem again by doing so. You can almost always spray WB over solvent w/o problems, but rarely ever the other way around.

 

[ChaoticBliss]

Thanks. I will try and find a supplier of that near me.

Do you think I should try an oil based stripper first since that was put on most recently? There are areas where only oil based sealer is on the concrete (areas that were bare when it was sealed). Or wil this stripper take off both?