How to Patch a Vinyl Pool Liner (Underwater or Dry)
Small tears and pinholes in vinyl can be fixed cleanly and last multiple seasons. This guide shows you how to confirm the leak, prep the surface, and apply a patch that seals tight — whether you can drain down or must work underwater.
DIY Steps to Patch a Vinyl Liner
- Step 1: Confirm the Leak Location. Use a dye syringe around seams, fittings, steps, and suspected tears with the pump off. If dye pulls in, you’ve found the leak. Mark lightly with a wax pencil.
- Step 2: Measure & Choose Patch Type. For < 2″ tears, use a precut round/oval vinyl patch. For larger/irregular tears, cut from sheet vinyl. Avoid square corners — round the edges to prevent lifting.
- Step 3: Clean & De-grease the Area. Gently wipe the liner around the tear with a vinyl-safe cleaner, rinse, and let it air dry if above water. Underwater: fan away debris so the adhesive bonds to clean vinyl.
- Step 4: Prep the Patch with Adhesive. Apply vinyl cement to the patch back (edge to edge). For underwater work, fold the patch onto itself (taco fold) with adhesive inward to reduce wash-off during the dive.
- Step 5: Apply & Smooth. Center the patch over the tear and press from the middle outward to purge trapped water/air. Smooth firmly with your fingers or a rounded roller. Hold pressure for 60–90 seconds.
- Step 6: Edge Seal (Optional but Recommended). Run a thin bead of vinyl cement around the patch perimeter and smooth lightly to reduce edge lift.
- Step 7: Cure Time. Avoid brushing/vacuuming the area for 24 hours. Full bond typically develops in 24–48 hours, depending on temperature.
- Step 8: Re-check Water Level. Mark the skimmer faceplate and verify level stability over 24–48 hours. If loss continues, repeat dye testing nearby; multiple pinholes are common.
Tip: If the tear is near a fitting gasket (skimmer/return/step), a patch may lift. Consider replacing the gasket and adding a gasket-to-liner seal — or schedule a pro repair.
What You’ll Need
- Vinyl patch kit or sheet vinyl + vinyl cement
- Dye syringe / food coloring
- Wax pencil/marker (pool-safe)
- Vinyl-safe cleaner & soft cloth
- Scissors (round patch edges)
- Optional: small roller/squeegee for smoothing
- Mask/goggles for underwater work