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Stopping a Leak

Pakmix® Stop Leak is a specially formulated blend of cement and other ingredients designed to stop the flow of water through cracks and holes in concrete and masonry. Sets in minutes even under water.

Tools Needed for Project: 

  • Pail for mixing
  • Hammer
  • Chisel
  • Putty knife
  • Trowel
  • Brush for cleaning
  • Eye protection 

Step #1:

Enlarge the crack’s width and depth to 3/4″, then cut an inverted V, using a chisel and a hammer. Thoroughly clean the crack with a wire brush.


Step #2: 

Dampen the area and mix Stop Leak. For best results, mix a small amount of Stop Leak with clean water and mix to a putty consistency. Do not prepare more than can be applied in two minutes.


Step #3:

As Stop Leak starts the hardening process, it heats up. For best results, wait for the Stop Leak to warm up and stiffen, then use a putty knife to press the material into the repair area. 


Step #4: 

Hold the material in place until it hardens, usually 4 to 5 minutes. Shave off excess material and keep damp with a light mist of water for at least 30 minutes.

Suggested Uses:

  • Stop leaks in concrete and masonry walls
  • Patch holes in cisterns and water tanks
  • Repair decks and swimming pools
  • Plug leaks around pipe and conduit 

Packaging & Yields:

One (1) pound fills approximately 17 cu. in. and will fill a crack approximately 3/4″ x 3/4″ x 30″ long. Packaged in 10 and 50 lb. plastic pails.

Please Read the Instructions and Warnings on all Packaging