If your brick mortar is ruined, you will likely need to completely replace it. Here's a quick guide on how to do that:- Remove the damaged mortar using a chisel and hammer. be careful not to damage the bricks in the process.- Clean the area thoroughly using a brush and water. Make sure all of the debris is removed so that the new mortar will stick properly.- Apply a layer of masonry cement over the area where the mortar was removed.- Place the bricks back in place and use a level to make sure they are straight.- Apply more masonry cement over top of the bricks, making sure to fill in all of the cracks and crevices.

If your brick mortar is crumbling or falling apart, the first step is to remove all of the loose mortar with a trowel or brush. Once it's clean, use a damp sponge to wipe away any remaining dust or dirt. Then mix up some mortar cement according to the instructions on the package. You'll want to use a stiff-bristled brush to apply the mortar cement to the damaged area, using a circular motion. Once it's applied, let it dry for about 24 hours before applying another coat. Make sure you allow ample time for each coat to dry completely before applying the next one.