Wall caps on a retaining wall create a finished look and prevent weeds and debris from building up between the blocks in the wall. They are typically glued on, using masonry construction adhesive. When you are removing a wall, making repairs or want to remodel the appearance of the wall, you will need to remove the caps first. A cap can be removed with a block chisel. Block chisels are designed to make clean cuts on all sorts of masonry. Take your time lining up the chisel so you can avoid damaging the blocks in your wall.
Start at one end of the cap. Locate the seam between the cap and the top edge of the final course of blocks.
Line up the chisel with the seam, and tap the end of the chisel with a hammer to make the first break in the seam.
Move the chisel along the entire length of the seam, tapping the chisel with the hammer. Work your way along the other side of the cap in the same manner.
Position the chisel at the end of the cap, and strike evenly along the end seam. Continue making even blows along the seam with the chisel and hammer until the cap breaks free. Lift the cap from the wall and set it aside.
Chisel off any of the remaining adhesive, using the block chisel. Hold the chisel at a slight angle, and tap the end of it along the remnants of adhesive to chip them off. Brush the surface with a wire brush to clean off any remaining debris.