A block is 225mm in height,should be able to work out the mortar beds,either working down from top of wall if whole block used, or up from bottom. Can use a small 5mm or smaller masonry bit to drill test hole in out of sight location, easier to repair,then use 12mm bit when you have found the mortar joint.
Wouldn't this of done the trick?... I found some in our shed https://flic.kr/p/2hVDkG8 If so, I should scrape all loose paint off,.... Put 2-3 coats on, prime and then paint? Unsure if this is meant to be used on bare wall or on top of paint
I think it's to go over the top of paint to seal... I will give it a go once the weather goes dry and the concrete drys out I say this I don't see how the paint could soak in
It's a clear water repellent like Thompsons water seal, would go onto unpainted surfaces such as listed on container and paint will not adhere to it.