I have lived in my current house for 20 years, the concrete driveways have never been cleaned. I never though much about it until I sold my 32' camper and noticed one side of the concrete in front of my shop was white from where the camper protected it and the other side dingy black and gray.
Knowing how tedious using the spray nozzle on my pressure washer to clean large expanses of concrete is I ordered a surface cleaner to fit my rig.
First I had to retrieve my pressure washer from my neighbor, I never used it, he needed one often so I let him keep it in his shop. While I had it I decided to change the oil and found he had never checked the oil level level while he had it, the dipstick has a tiny smidgeon of oil on the very end. When I drained the oil there was less than a cup, dang. I topped off the crankcase and started the motor, it ran OK, I guess any damage done from lack of oil will come back to haunt me later.
I spent half a day going back and forth to Home Depot trying to find quick disconnects that would couple the surface cleaner to my pressure washer wand. On my third try I finally had pieced together the right parts to hook everything up.
The surface cleaner actually worked and worked quite well, slow and steady passes left a streakless concrete surface clean of all but the toughest stains. I did a few touch-ups for the very few places I had missed after the pad dried out. In the picture you can see the difference between the pad in front of my garage doors and the uncleaned filthy driveway I haven't cleaned yet. I quit for the day while working on the sidewalks, my botched hip replacement told me it was time. The sidewalk picture shows the daylight and dark contrast between the cleaned portion and 20 years worth of stains.
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