A good filler for a crack in an external wall?

[Udhi]

Hello,
My end terrace has an external "perimeter" built in the 90s, by the previous owner.

The part where it meets the house's wall doesn't seem to be stitched to the house's brickwork. Consequently, there is a vertical crack at this joint in a v-shape. This crack goes straight through and covers the top 1/4 to 1/3 of the wall, and let's in water into a shed we built on the other side, using these walls.

Is there some kind of pot or potion that I can inject into this crack to seal it properly? The crack is not getting any bigger, nor the brickwork loose.

Any help appreciated?

 

[^woody^]

Clear silicone

Or a suitable coloured polysulphide mastic

 

[^woody^]

Clear silicone

Or a suitable coloured polysulphide mastic

 

[Udhi]

Thanks Woody - twice over!

I thought there was a stronger solution required, will get looking for this polysulphide mastodon...thingy asap.