Cleaning oil stains on garage floors can be a pain. They are an eye sore and the enemy to anyone that likes to maintain a clean garage or driveway. With all the technology available in cleaning products today, you would think the frustration at removing oil stains would be a thing of the past.
Unfortunately though, concrete is a very porous medium and likes to absorb oil like a sponge. If allowed to sit for a while, it will soak into the concrete and do a great job of frustrating the efforts of even the most determined to remove it.
Fortunately for us however, there are a few highly successful methods for removing even the toughest of oil stains from garage floors and driveways. These methods also work very well if you need to remove oil stains for a garage floor coating or sealer application.
Cheap concrete oil stain removers
If you have an oil stain that is fresh or fairly recent, one of the best cleaning agents to use is Tide powdered laundry detergent. Tide used to be NASCAR’s standard oil cleaning agent on the track until the more sophisticated oil-dry products were developed. Dawn dishwashing detergent works well also.
Start by blotting up any heavy residue that may be on the surface and then pre wet the stain as well as the surrounding area. Oil that is freed from the cleaning process can migrate and cause a secondary stain on the dry concrete if you don’t do this.
Next, mix a strong solution of the detergent with hot water in a bucket. Pour it onto the area to be cleaned and then sprinkle more detergent directly onto the oil stain itself. Use a good stiff bristled nylon brush and start scrubbing away.
Be sure to let the soapy solution sit for a few minutes but do not let it dry. Letting the mix sit allows it to penetrate into the pores of the concrete and emulsify with the oil, effectively lifting it out of the concrete.
Once it has sat, use your garden hose with a high pressure nozzle to rinse away the solution. The water pressure helps to lift the remaining emulsified oil out of the pores and remove the stain. Using a wet/dry shop vac on the sudsy solution and then rinsing works well also.
This inexpensive method works well for many oil stains in preparation for your garage flooring of choice.
Stubborn concrete oil stain removal
For more stubborn oil stains or stains that have sat for quite a while, we recommend purchasing a strong concrete degreaser. Degreasers work well at penetrating the stain, breaking down the oil, and drawing it up and out of the concrete. Oil Eater is our favorite. You can also find others here at Amazon.
Another tip that works well on really tough stains is to use an absorbent in conjunction with a degreaser. Kitty litter is the old standby, but there are much better products labeled as oil-dri. You can find them here.
Start by pre wetting the area to be treated with hot water. Next, mix a very strong solution of the degreaser and then pour it directly onto the stain. Scrub the area well and then let it sit for at least 15 minutes. This allows the solution to work its way into the pores of the concrete and break down the oil. Do not let it dry. If it starts to dry before the time is up, add a little more solution and scrub again.
Now, while the area is still wet, scrape off any heavy suds or standing water with a dust pan or towel. Next, pour a liberal amount of oil-dri or kitty litter directly onto the stain and grind it into the concrete with the soles of your shoes.
Oil-dri is a natural poultice and will work by drawing the solution out of the concrete and absorbing it. Let it sit for at least overnight. Make sure that you have enough on the garage floor to absorb it all. If it all turns dark from being wet, it will stop working. The next day just sweep up the kitty litter and the oil from your stain should be gone.
Sometimes for stains that have been in concrete for years you may have to take a tougher approach. This is only recommended if you have tried everything else.
Using the above method, you will want to use a solvent like kerosene to pour onto the concrete. The solvent does a good job of soaking into the concrete and breaking down the oil. Fumes from solvents can be very flammable so make sure you turn off any pilot lights or open flames before you do this.
Once it has soaked into the concrete, cover the stain with a coating of pure Portland cement. Do not use premixed concrete or mortar mix. Portland cement is a fine hygroscopic powder that will absorb the oil. It’s best to let it sit for a week or more to work properly. You can cover it with a garage floor mat or cardboard if you like while it sits. When ready, just sweep it up.
Other recommend products
One product that we can recommend that does a great job of removing smaller embedded stains is Pour-N-Restore. It’s made with a strong citrus degreaser and a non-leaching absorbent. You just pour it on the stain, let it sit till it dries to a powder and then sweep it up.
It works real well for those spots on your garage floor where your car may have been dripping oil. What’s nice about it is that you don’t need anything other than a broom and dustpan to use it.
Another successful type of product is an all natural process that works with bioremediation. Micro-organisms go to work by breaking down and eating the hydrocarbons of the oil and restoring the concrete to its original appearance. We’ve used a couple of these before and it’s amazing how they work. Some even work well at removing stains from asphalt.
Eximo is one such product. It’s a dry powder that you apply and sweep over the stain. Give a few days to work and the stain will disappear. Two applications usually is all that is required.
The other is Terminator-HSD. It’s a dry powder that requires a mist of water to activate the live bacteria. Again, it takes a few applications to work on the toughest of stains, but it works. And the best part is there is no scrubbing required.
Just remember, any oil stains that have been on your garage floor for a period of time may still leave a faint shadow or outline of where the stain once was. If you are quick to treat them however, you shouldn’t have any evidence of a stain being there at all.
Once all the stains are removed, now would be a good time to take some preventative measures to seal your floor to protect it from anymore spills or drips. You can also elect to put down a garage oil mat as well to make your concrete that much easier to keep clean.