Walls and Ceilings - Another texture question

Have two rooms with old popcorn texture on ceiling that I have scraped off with trowel. I want to do knockdown using sheetrock mud to texture ceilings and also wall in these rooms. Should I use a "kilz"-type primer on the old ceiling before texuring? Also, should the walls be primed before texturing; I have done quite a bit of drywall repair work on these walls? After the texture will I need to prime again before finish coat of paint? Plan on using airless sprayer for the priming and painting, will this work? Sorry for the long question, but thanks for your help. Ted

I'd prime it all either prior to or with the knockdown coat. The paint makers, don't recommend this, but I have done it with good result. Most will recommend priming before and again after texture is done.

Good luck.

DONT use kilz. Something weird happens with the whole oil and water dont mix and it doesn't work right. If you want to prime use a water base. I guess kilz 2 could work.