Sealing windowframe

[daveaspy]

I've a couple of windows like this - where they have been sealed with mortar (its hard and brittle) which is now crumbling off. I'm not sure if the bottom was also the same but previous owners have tried to replace it with frame sealant as that's pretty ropey too. What's the best thing to do with these - remove whatever is on all sides and redo with frame sealant? I was thinking the acrylic stuff from screwfix

 

[DAZB]

Using a frame sealant may not cover the wide channel created by the previous substance and you may be better using a trowel mastic which will give a nice firm fillet and comes in a range of colours.