Over the past 20 years, we’ve received many questions from customers on repairing inflatable kayaks, locating leaks or adding d-rings and mounts. Just recently, we stumbled across a great tech sheet put together by Aquaglide a manufacturer of inflatable kayaks, standup paddle boards, and a new Backwoods lightweight, packable kayak series. We are reprinting the tech sheet below – read on to find out how to locate a leak in an inflatable kayak, what materials and repair methods to use and when to use them. As long time retailers of inflatable kayaks and paddle boards, we have expanded this to include some of our own AirKayaks tips.
GENERAL PVC REPAIRS – updated 07/30/2020
NOTE: The following instructions are for patching a basic leak on a PVC inflatable, typically a puncture or cut. More complicated repairs such as those near seams and corners, may require special repair techniques which are beyond the scope of this article.
Some Helpful Items and Where to find them
Tear-Aid – Tear-Aid Type B is a self-adhesive patch material that’s widely available online and at nationwide retail outlets like Walmart, Ace Hardware, AirKayaks, REI and more. Great for relatively long-term repair of punctures on all types of PVC products. Clear, non-toxic and easy to use.
Aquaseal FD– This is a liquid sealant that can be oozed into very small cracks, edges and pinholes. Widely available online and at nationwide retail outlets. This stuff is a little messy to work with and may be best applied using a small plastic irrigation syringe from the drug or hardware store.
Shoe Goo, Clear– Yup, seriously. This is a very thick vinyl-based adhesive that can be used for quick, short-term plugging of small holes on low pressure items. Widely available online and at nationwide retail outlets like Walmart, Lowes, Walgreens, Dick’s, REI and more.
Fabric Reinforced PVC – Reinforced PVC, or tarpaulin, is commercial grade material that is the basis for most of Aquaglide’s Duratex products. The strongest and most durable repair for Duratex items is generally to patch with material of the same type. This material can be found in the repair kit included with your Aquaglide product or purchased from an Aquaglide distributor. In a pinch, similar material can be found online, or at marine stores where RIB dinghies or whitewater rafts are sold or serviced. If you go this route, DO NOT use patch material or glue intended for Hypalon, which looks almost identical, but will result in a gooey mess when combined with PVC.
Contact Adhesive– For those choosing to repair with a reinforced PVC patch (see above), using good glue is critical. We recommend HH-66 vinyl adhesive, which is available through Aquaglide, and also widely available online, through Walmart and many local auto parts stores where it is used to adhere auto emblems. The 4oz and 8oz sizes typically have an applicator brush in the cap – perfect! If not, you’ll need a small disposable brush.
Solvent– Don’t skip. While smelly and admittedly hazardous to health, it’s important to clean surfaces with solvent before making a long-lasting repair. MEK (methyl ethyl ketone) is the best solvent for PVC repairsas it chemically preps the surface, but Acetone will also work. Rubbing alcohol/isopropyl alcohol works in a pinch, but is not nearly as good at removing oils on the surface which can spoil adhesion. In North America, all of these products can be found online and at local hardware or home repair stores.
Some Other Stuff– For Tear-Aid or Reinforced Patch you will need sharp scissors or a razor knife, a bit of sandpaper (medium grit), pencil or china marker. A clean rag is helpful for any repair. You may also want liquid dish soap & sponge (to find a sneaky leak), and a respirator and gloves (to keep the solvent away from you). Please note: Do not use steel wool to abraid the surface! It has oils on it which will spread around and mess up the lamination. Also, small fragments of the steel will break off and embed in the (relatively soft) PVC surface. Use 120-150 grit sandpaper or (better yet) emory cloth. The emory cloth is better because it doesn’t leave as many particles that have to be cleaned off.
LOCATING LEAKS
- You may know right where the leak is (lucky!). If not, you first need to locate the leak. To do so, fully inflate the product. Some leaks are hard to find at lower air pressures, so re-inflate periodically while looking.
- Use a soapy water solution (50%/ 50% dish soap & water) and a clean rag or sponge to check for leaks. Work slowly around the product spraying or swabbing-on soapy water solution. Listen carefully and look for growing bubbles, which indicate a leak. Don’t forget to check seams and around the valves.
- Once a leak is confirmed, dry the area well, mark it with a pencil or china marker and prepare to patch.
VALVE LEAKS
Military Valves
- If your kayak has a military valve and the leak appears to be coming from around the valve, it is possible that your valve is loose! Use the valve wrench that comes with your kayak to tighten it and then check overnight to see if that solved the problem.
- If the leak appears to be coming from inside the valve, check the interior and push on the plunger (military valve) to make sure that dangling threads or sand is not lodged in the valve flap, impeding a tight seal. Blow hard or use a soft brush to remove the culprit. Always remember to screw on the valve cover to prevent sand/particles from getting inside the valve.
Boston Valves
- If your kayak has a Boston valve and the leak appears to be coming from around the valve, please read our article, How to Use and Troubleshoot a Boston Valve for Inflatable Kayaks.
PATCHING LEAKS
Please read through General PVC Repairs above to see what materials will work for your repair.
Tear-Aid Type B: (Easy Options)
- With the leak located, cut a Tear-Aid patch using sharp scissors. Round the corners slightly (approximately ¼” radius). The patch should cover 1″ (2.5cm) outside the leak area in all directions.
- Use solvent and rag to clean the patch area. Dry with a clean cloth or allow to air-dry.
- Peel back the paper backing to expose a section of adhesive. Align the patch and apply pressure to stick in place. Peel back the remaining paper backing material. Avoid trapping air bubbles under the patch.
- Rub firmly from the center toward the outer edges of the patch, making sure to press all sections firmly in place.
Aquaseal FD or Shoe Goo (These products only work for small holes.)
- Clean with solvent about 1” around the hole.
- With the item deflated, cover the hole with Aquaseal FD or Shoe Goo making sure to cover approximately ½” in each direction around the hole. With Shoe Goo you may have to use a slightly wet, gloved finger or tool to press the goo flat.
- Allow to cure for time period specified by the manufacturer, then inflate.
Using Fabric Reinforced PVC/Patch Leak
- Deflate the product. Arrange the work surface so that the repair area is most accessible.
- Cut PVC patch material to size using sharp scissors or razor knife. Round the corners slightly (approximately ¼” radius). The patch should cover 1″ (2.5cm) outside the leak area in all directions.
- Clean with solvent a little beyond the gluing area. Also clean the back of the patch material.
- Use sandpaper to rough up the surface to be patched and the back of the patch material.
- Clean with solvent again to quickly remove sanding residue from gluing area and the back of the patch.
- Dry-fit the patch and use pencil or china marker to outline where it will be located.
- Use a small disposable brush, or HH-66 applicator brush to apply a thin, even layer of glue to the repair area. Cover completely, but glue only within the outline.
- Apply glue to the to the back of the patch making sure to cover the area completely.
- Allow glue to cure briefly (30 – 60 seconds) – just until the surface glazes slightly.
- Repeat 7-9 to add a second coat of glue in the same way.
- Align the patch over the repair area using the outline as a guide. Once the 2 surfaces touch, the bond will be immediate, so take care.
- Carefully apply the patch to the repair area, starting at one corner and working outward.
- Use very firm pressure to rub the entire patch area and the edges of the patch for at least 1-2 minutes.
- Allow to cure for at least 12 hours before inflating.
You can also see our article on Attaching D-Rings to an Inflatable SUP, which uses the same general approach.
Thank you, Aquaglide for taking the time to put together this information!