Painting over stained plaster

[CMS16]

Hello -

After some advice from more knowledgeable heads!

Fresh plaster skim on kitchen ceiling. Leak in bathroom during pressure test of new heating system. Also a few yellow stains coming through on plaster (previous leaks?).
Leak now sorted, but can't afford reskim again. Ceiling dried out now.

My question is - I've gotten cover stain primer - should I put this directly on the plaster? Or do a watered down emulsion first, same as everywhere else and then the cover stain primer?

Just hoping the stains don't come through on my freshly painted kitchen ceiling...

 

[Robbie uk]

Thin the Coverstain a bit then straight on. A coat of emulsion first wont do any good at all. It will kill the stains, as will Zinsser 123 BIN and oil based undercoat.

 

[London Mike 49]

We have just refurbished our house and had exactly the same problem as you, fortunately I have successfully dealt with stains like this before ( another story! )
The best way I have found ( having tried all sorts of propriety stain blocks ) is to give the stains a coat of oil based undercoat, let it dry overnight and then paint as normal.
Only once have I had to give a stain two coats , and that was when the stain was dark brown.

Mike