weak wall

[North]

HI,
I am stripping the wall paper of all the bedrooms of my new house in order to paint them. One of the walls has got a crack in the centre of about 45 degress although not to big (about 80cm) and I have removed the plaster and exposed all the bricks in an area of around 0.7sqm. It is part of a doube wall as it is the side that separates from the extrior of the house. If you look from outside you can see that the crack has also afected slightly the extrior wall. Now going back to the internal wall with the crack I noticed that the cement that were used to join the bricks is really soft (I could just remove it with a nail If I wanted). I have two questions:
1-Is that normal or is the cement old and has weakened over time?
2-I can not budget for a profesional to come and fix it for me, not at the moment anyway, so I am looking for the best repair i can do my self. I am thinking to just fill up the hole with some mortar and then skim it with plaster or something similar

THe house is a 1930 although I ignore how old the walls are.
Does this sound reasonable or has anyone got a better suggestion?
Many thanks,
North

 

[PrenticeBoyofDerry]

It sounds like there has been a little moment in the house, doesn't seem that bad. If less than a metre and no other evidence of this.
It's likely that it's been hidden behind the wall paper for years.
The mortar in the joints will dry and dust up over time, if they are a great concern you could rake them out and repoint.
I would try and use a like for like as far as the base coat for plastering is concerned, ie if it is a sand/cement render use that or a browning if plaster.
Then you can finish it off with a two coat skim off multi-finish.
Damp down the walls prior to applying your base coat.

 

[North]

Thanks. I do not want to re-set the bricks as I would have to do it with the whole wall. I am just concerned because the wall looks like I could bring it down just by kicking it. I just hope the external wall is solid.
Cheers,
North

 

[PrenticeBoyofDerry]

Well if you do kick it and it comes down, you now you have problem!