I have a problem with horizontal and step cracking in my concrete
block basement walls. The step cracking looks relatively minor, but
there is a nasty looking horizontal crack most of the length of one
wall. It is close to a quarter inch wide in some places and located in
the fourth joint from the top which is about two blocks below the soil
line.

The cracks have never leaked. I did do a quick job of repairing the
largest crack two years ago but they recracked. I'm guessing from the
location this is due to freezing/thawing.The walls are slightly bowed
- if i am measuring properly, there is about a half inch of
displacement. I believe the displacement has increased only slightly
since 2002 when I had an expert evaluate my basement before i
installed a rec room. (The large crack was discovered at that time
under some wood paneling - that's why i called the foundation expert)

We are now getting the house ready for sale. I am considering having
the crack tuckpointed and disclosing the repair as well as the
existence of the crack behind the finised part of the basement. I am
pretty sure the cracks will reappear after the next freeze/thaw and I
do not want a future lawsuit. I'm going to have some contractors in
this week, and i'm wondering if they will try to talk me into steel
posts or excavating.

The walls without the large crack also show some displacement. Would
anyone know what amount of wall displacement is considered accepable?
Also, i get the geneal idea of determining displacement by dropping a
plumb and measuring distance to the wall. But at what levels would I
measure? The top, middle and very bottom measurements are all
different. Is it the greatest dufference?

Thanks in advance for your advice/opinions.

Rob