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How to Clean  Old Oil Stains from Concrete

How to Clean Old Oil Stains from Concrete

Posted by Mike Hernandez on Jul 22nd 2021

Heavy oil stains can build up in garages, shops, drive through areas and warehouses.  We are frequently asked the best way to clean these areas. 

We recommend the following process:

  • If there is a build up of oil stains on the surface, we recommend removing as much of the heavy oil as you can with a stiff brush first to allow the pores to open which will allow the cleaner to penetrate.  Sweep up and remove as much as you can.
  • Spot treat the heavy areas with SealGreen Oil Cleaner Degreaser. Allow it to soak for 10 minutes before treating the rest of the surface.
  • Apply our SealGreen Oil Cleaner Degreaser to the entire surface. Watch the following SealGreen Oil Cleaner Degreaser application video -
  • Rinse the area to be cleaned using a pressure washer. The SealGreen Oil Cleaner Degreaser will biodegrade the oil breaking it into parts which are safe to wash into the sewer.
  • This step will remove most of the oil on the surface and some of the oil which has penetrated the concrete. Oil stains are extremely hard to clean from the surface because once you have cleaned the surface, the oil inside the pores of the concrete will resurface and the oil stain reappears.
  • Once that you feel you have cleaned as much as you can clean with SealGreen Oil Cleaner Degreaser, allow the concrete to dry completely naturally.
  • Once the concrete is dry, apply SealGreen Gray-Out Waterless Oil Cleaner to the remaining oil stain in the concrete. Watch the following Gray-Out application video
  • The Gray-Out will stick to the remaining oil stain. The enzymes in the Gray-Out will follow the oil into the microscopic pores of the concrete eating all the oil that can not be removed by washing. The enzymes then die, turn into CO2, and evaporate.
  • The process is slow but Gray-Out is a concrete gray color and will blend in color with the existing concrete. It will remain in place until all the oil is removed, or it has eaten as much as it can. Depending on the amount of oil in the concrete several treatments of Gray-Out may be required.
  • The Gray-Out, over a period of a couple of days, will stick to the concrete until it eats the oil. The Gray-Out should be applied just to cover the stain so that daily traffic over the cleaner will not track or affect its performance.  Many commercial places use this process on drive-throughs, parking lots, driveways, and sidewalks to maintain the property looking great for their clients.
  • One last thing, to avoid repeating this process frequently we recommend sealing the concrete with SealGreen Concrete Sealer with Salt Defense Technology. This will prevent deep penetration of oil and will make regular cleaning easier and faster. Watch the SealGreen Concrete Sealer application video
  • Please call 800-997-3873 if you have questions, to order products or need further technical assistance with your project.