Without question, tire issues are the most common vehicle problem encountered in overland travel. Punctures, slow leaks, damaged valve cores and tire beads losing their seat on the wheel. Developing your skills on tire repair is an essential component of preparation and should include:
- Breaking the tire bead with a jack
- Using plugs and insertion tools
- Stitching a tire carcass.
- Installing a patch (large carcass repair)
- Reinstalling a tire
- Reseating a bead on the wheel
- Repairing valves and cores
There are of course other skills related to wheels and tires, but those are the big ones. For this article, we are focusing on the process of reseating a carcass bead to the wheel. Most wheels used on 4wds include a welded, formed or cast safety bead that helps the tire remain on the wheel, especially at low pressures. However, low pressures required in some conditions, like driving in deep sand necessitates low tire pressures and potentially high travel speeds. This generally exceeds the ability of the tire construction and wheel safety bead (which is relying on internal pressure) to keep everything together. In the video shown here, we were having some fun on the dunes in Australia at higher speeds with a heavy Toyota Land Cruiser. The cameras were rolling and we were hoping for some big fans of that bright red sand for an article in Overland Journal. One particularly fast turn resulted in a flat. Typically the outer bead is the only one to pop free, but higher speeds or driving any distance with the flat will also loose the inner bead as well. That was our situation, but since we had the experience and proper tools, we were able to reseat the bead and still make it back to the Prairie Hotel for a feral feast. The video shows it best, but here are the critical steps.
- Safety: Make sure the vehicle is safe and stable. Wear gloves during all steps that can cause injury (some steps require fine movements, like handling the valve core). Use extreme caution during jacking and ensure vehicle is stabilized before initiating repair.
- Jacking: Jacking can be performed with either a bottle jack or HiLift. The biggest challenge in sand is ensuring you have a proper jack base to distribute the load on the soft surface. Jack the corner with the flat until the tire is off the ground. The height needs to be slightly higher than the inflated diameter, as you will need to run a strap around the tire.
- Stabilize: Stabilize the vehicle with a suitable wheel chock (rocks and wood can work in a pinch) to help prevent movement or rotation.
- Clean the tire and wheel bead as much as possible, typically with compressed air or water (air preferred).
- The tire carcass may be collapsed (flattened) and will require some pressure from your hands and/or the ratchet strap to come back into shape. Use caution and keep hands out from under the tire.
- Run the ratchet strap around the circumference of the tire carcass, with the strap situation at the centerline of the tread face. The ratchet should be a heavy duty unit with large handle if possible (for leverage)
- I like to spray or splash water around the safety bead of at least the outer bead of the tire and wheel. This helps the tire slide past the safety bead and helps it obtain a faster seal.
- Begin ratcheting the strap tight around the tire. As the pressure increases the carcass will begin pulling in at the center of the tread face, which will force the tire beads outward and against the wheel.
- Pull the valve core and attach the air chuck to the valve stem. This can be done without a storage tank, but is much easier with one (volume). A fast compressor also helps, but is less important than the tank. Open the air valve (I use a PowerTank Advanced Air Systems unit with gauge, chuck retainer and coil hose). Link: Powertank Gauge
- When the air valve opens, you will hear air rushing out between the tire and the wheel. Start pulling and pushing the carcass against the wheel by holding the tire at the tread. This takes some practice as the movement is relatively gentle and needs some control. You are attempting to get the bead to seal, if even momentarily because of the rapid rise of internal pressure.
- You will know when the seal is achieved, as the air rushing out will stop.
- The next step is to bring internal pressure up to the point that the tire bead fully seats against the wheel. This is usually accompanied by a pop as the tire slips past the safety bead and up against the wheel. There may be two pops if the inside bead also seats. Run the pressure up to highway settings and shut off the compressor. Listen for air leaks and inspect that the tire is fully seated against the rim on both sides.
- Remove the ratchet strap
- Pull the air chuck off, and if the valve core had been removed, all the air will come rushing out. No problem, as the tire is now fully seated.
- Reinsert the valve core and air up the tire to the required pressure (which may be trail pressure or highway pressure).
- Lower the vehicle safely and inspect all tools before properly stowing them for future service. Reinspect the tire pressure before driving on.
So, you can follow the above steps, or just do this. . .
Resources: Extreme Outback – Ultimate Puncture Repair Kit – Link:
http://www.extremeoutback.com/product/27/Ultimate+Puncture+Repair+Kit.html ARB Twin Compressor With Tank – Link: http://store.arbusa.com/ARB-Twin-High-Performance-12-Volt-Portable-Air-Compressor-CKMTP12-P22666.aspx ARB Speedy Seal Tire Repair Kit – Link: http://store.arbusa.com/ARB-Speedy-Seal-Tire-Repair-Kit-10000010-P3580C17.aspx