Basement walls and drylock

[dfuze]

I drylocked my walls last year and most are fine but in one section (spans about 2' high by 10' long) I've got blistering and white powder. I scraped it all off but am wondering the best way to prep it before reapplying the drylock.

Pic in case it helps in the solution.

 

[feralkid]

This is probably the white powder you are experiencing:
http://en.wikipedia.org/wiki/Efflorescence

Hopefully this will lead you in the right direction, as I only rarely encounter it where I live.

 

[MagnusTheBrewer]

Drylock by itself on interior basement walls doesn't do much but guarantee you will need to do it every year.