On Jan 18, 2:29*pm, jhiker wrote:
I have an old concrete-section garage. Water pools outside at the base
in a couple of places and eventually works it's way between the walls
and the base to the inside.
I've had a stab at filling the gap with a bit of crude pointing to no
avail - it may delay it slightly but it still comes in.

Might 'trowel mastic' be the answer?
Any other bright ideas?

These garages normally have a cement fillet all the way round on the
inside against the walls. This can be painted with epoxy paint. As
someone else said, drill hole through the base where the water puddles
on the outside & let it drain away. Also have gutters and down pipe to
convey the water well clear of the slab.