Paint goes yellow and stinks

[Bored Beanz]

Hello!!! I have used white Crown paint on newly plastered walls. (I have cleaned the walls with sugar soap first and left them to dry) A few hours later yellow stains have appeared and they stink.
Any idea? HELP!!!!
Beanz

 

[Zampa]

What type of crown paint?..gloss matt silk satin?

 

[Bored Beanz]

Pure Brilliant White Matt Emulsion Crown. Just one coat....

 

[JohnD]

is this house more than 60 years old?

what was on the walls before you painted them?

D*******R

edited - my mistake, these are newly plastered, so no old surfaces, right?

 

[Bored Beanz]

That's correct, the walls were plastered 4 weeks ago. The yellow stains appear in patches at random. (I had the same problem upstairs where the walls are about 60 year old but I though I didn't clean them properly and I have scraped the paint off now. Haven't tried to paint them again yet)

 

[Zampa]

My guess is that the walls were not properly dry

Try a thin coat of undercoat over them...or just a patch to start with and se eif that works when you put emulsion back over it

 

[Bored Beanz]

Can I put it on top of the smelly emulsion or do I have to scrape everything off, you think?

 

[Zampa]

Leave the wall to dry out a bit longer..

It mught be worth getting a damp metes they are pretty cheap ans will tell u if the wall is still damp