garage floor paint

[spinny]

Planning to finally paint the garage floor - 15 year old slab with typical engine block droppings and wheel smudge.

Paint co instructions were to remove all the oil / stains before applying epoxy paint - even suggested using Simple Green HD to degrease. So after 4 tries, although now somewhat less vibrant, the 'stains' are still there - and a shoulder shrug from Simple Green.

Anyone have a good plan B???

Really don't want to grind it. But anyone know a grinder just in case?

[RonG]

From what I recall when I painted mine (15+ years ago), you don't need to remove all visible traces of the stains, which can run fairly deep into the concrete. You just need to be certain that what remains is not hydrophobic. Once you've accomplished that, it should accept the paint with no trouble. (This assumes you're using a two-part epoxy paint.)

Keep scrubbing, rinsing and repeating until there is absolutely no beading over/around the stains. Check again after etching; if the rinse water pulls away from the stains again, repeat the whole process in that area.

[dngo]

Many good floor epoxies strongly recommend the use of muriatic acid to clean the concrete. You will have to flush thoroughly with water and allow to completely dry before applying the epoxy.

Dave

[RealM3E30]

I used to use Muriatic acid on concert pools to prepare for paint, just be careful with it, comes by the gallon. I would also try using a power washer with the Simple Green ? Let us know how it works out, mine is next !!

[Myro]

ive been using the products at home depot on the concrete floors and they hold up and work really well under heavy use (ie fork lifts and pallet jacks )

[victory1auto]

There us a product by Chomp called "Pull It Out" that will greatly reduce if not eliminate oil stains in concrete. Home Depot has it.

Re painting your floor, the instructions for the 2-part paints I have used required etching the concrete surface with a muriatic-acid solution. I don't know how good the adhesion will be without proper surface preparation. If you etch the surface, you will need to allow sufficient time for drying after the etching-flushing process.

[spinny]

Cleaned the floor again with Simple Green HD Pro. Simple Green rcmnded adding baking soda. Why? I found a YouTube video on garage floor prep pre-paint that suggested using a hi PH (alkaline) solution to remove oil. pH of water ~5, baking soda ~7. So I also added ammonia - Ph ~11. Took the oil right off. Scrubbed it with a round floor sander rented from Home Depot with a rough 'plastic' abrasion disk. Worked well. Rinsed 2-3 times with power washer. Since the concrete surface was in good shape, no need to etch. The sanding disk also helped. Corotech suggested using Simple Green HD Pro after I complained that their cleaner was $50 / gal.

Used 2 coats of Corotech V440 epoxy concrete paint. Benjamin Moore bought Coronado 3-4 years ago. Corotech rcmnd using their V156 sealer / primer first. So far looks good. But the paint really began to become viscous after 2 hours, so had to hustle.