stubborn oil stain

What's the next suggested step when EBC cleaner + Hot Water combination does not get rid of old oil stains? The client was more than amazed with the how her stuff turned out by me on the other hand have too much OCD to let this old stubborn stain get the best of me. We mixed the EBC as suggested on the forums and allowed it to sit as recommended. Almost instantly, EBC went straight to work and you could see it pull up the stains. However, I'm not sure as to what options are there (if any) when stains don't come out all the way. The old stains are about 20 years old and did look a lot worse ... like I mentioned earlier the client is very happy ... this is me on the other hand try to take a learning curve from this.

A few more applications of your degreaser and more dwell time will lighten it up some more.

Its never going to come all the way out. hit it with degreaser, scrub with a deck brush, hit with hot water. Repeat a second time if you want to (you will get better results if the concrete is dry). After that, its as good as its going to get.

Oil stains sitting there for a while become somewhat permanent, never promise they will be removed, only they will look better or you might be working for free for some customers and even possibly them bad talking about you as you say you can do something but did not do the job.

There are many reasons why the oil stains the concrete and we all have been looking for the miracle chemical to remove all the stain out of concrete but so far nobody has come up with it yet so we all just make them look better than they were and they will have a shadow.

I agree with Chris. Any proposal I write where the customer wants gum, oil stains, rust stains, ect removed I always word it as "attempt" to remove oil stains, gum, rust stains, dirt and debris. This way you're covering yourself and you're basically telling the customer that you will do the best you can.

I couldn't find the thread but someone was show a video where they removed stains with gas and blow torch.

I was not able to find it on PWI, however here is the link to the video showing it http://www.youtube.com/watch?v=mITcdljaDe0

One thing I have found is if the source is contained, and the free oils and sediment in the oils are removed, that the Arizona sun can significantly reduce any long term staining. I would guess I would be similar anywhere the sun is bright. If I use my preferred chemical, Ultrite degreaser, the results are nearly 100%.

Where do you get your Ultrite from Scott?

White cap construction