Operating a lawnmower with a torn grass-clipping bag is dangerous because small objects, such as sticks, can escape the bag as projectiles and hurt bystanders and operators. Fixing the tear is a much less expensive alternative to purchasing an entire new lawnmower bag. A swimming pool patch kit and a few household items are all that is needed to make repairs and return to mowing.
Place 1 tablespoon of dish soap into a bowl. Add 4 cups of hot tap water and mix the ingredients with a toothbrush to form suds.
Remove the lawnmower bag from your mower. Most bags clip onto a metal retaining bar with one or more clips. Empty the bag if it contains grass clippings.
Place the bag on a flat surface, such as a workbench or table. Scrub the area of the tear with a toothbrush and about 3 inches around it with the dish soap solution. Clean the inside of the bag with the solution in the same manner. Dish soaps have a grease-cutting agent to clean the bag material of any dirt, debris and oils.
Wash the soap solution off the bag, both inside and outside, with a garden hose. Dry the area of the tear with a towel and allow it to completely air dry.
Cut two pieces of vinyl swimming pool patch that is 3 inches larger than the tear on all sides, using scissors.
Put on latex gloves to protect your hands from glue. Turn the lawnmower bag so the tear is face down on the flat work surface. Apply the patch kit glue to one of the patches. Allow a few minutes for the adhesive to become tacky. Reach inside the bag, center the patch over the tear and press it down firmly.
Turn the bag over with the tear facing up. Apply adhesive around the tear and on the additional patch. Allow the glue to become tacky. Press the patch onto the outside of the tear in the same manner as the one inside the bag.
Turn the bag over again with the patches facing down on the work surface. Place a brick on top of the bag over the patches to help them stick. Leave the brick on the patches for about 30 minutes for the adhesive to cure.