Yellow spots bleeding through white gloss paint

[bikeit]

Two years ago we got all the door frames architrave and skirting replaced upstairs, the replacement wood was just standard white wood which was painted white gloss, but recently i have noticed yellow spots some big some small bleeding through the gloss coat, so am i right in thinking the decorator didn't use any knot sealer on any of the woodwork?
If this is the case what is the best way to treat these spots to stop them reappearing again?

 

[Bonni]

Knotting fluid wasn't applied to the knots before painting.

Sealing with Zinsser’s BIN can give reasonable results.

I know a guy who applies a two part filler (like car body repair) over them but I've never tried that. If it's too thick to a small area, it'll stand out when painted over so thin and slightly further than you think.

 

[bikeit]

When you say reasonable results do you mean the spots will return or?

 

[opps]

Even if you use a shellac based "knotting" product (such as BIN/etc) you are not safe from weeping resinous knots.

In my experience, water based primers can be quite forgiving, but if a knot wants to weep, i am not aware of anything that will stop it.

It a PITA but the only way of dealing with knots is to drill/extract them.

 

[nauseous]

Is the resin highly flammable? If not, why not try a blow torch or better still an elect hot air gun to draw it out, scrape it off then fill and sand?