Powertank On Board Air
Dean ‘Old Skool’ Bradley
On Board Air (OBA) systems offer what no other tool or equipment can, the ability to air up tires in the backcountry - and that makes them an ‘Off-road Essential’. The ability to reseat tire beads, air up tires after puncture repairs and for some OBA systems - the option of running air tools, is simply irreplaceable. From stock Jeeps to competition Rock Buggies, On Board Air may be found in all types of 4x4 vehicles, yet these OBA systems can be as varied as the vehicles they ride in. In this article of Off Road Essentials we will be discussing the three common types of On Board Air systems on the market today and offering some clues as to the different capabilities of each system.
Regardless of what OBA system you decide is the right one for you and your ride, know that once you begin taking on the challenge of taming tough terrain, an OBA system should be considered an essential part of your equipment. With it, you can begin pushing the limits of lower tire pressures for superior off highway performance, without having to rely on others to supply you with some air if you slip a bead while attempting to master the best off road air pressures for the tires.
Tire punctures can even become a non-issue with an OBA system, a premium tire repair kit, and some practice in the driveway using them together. If the need to expedite trailside repairs is a re-occurring theme in your wheeling world, perhaps a system fit to run air tools should be in your sights. The three common OBA systems found on your typical 4x4 trail run today are;
1) The CO2 powered self-contained portable OBA system.
2) The 12 volt (vehicle battery) electric powered OBA systems.
3) The vehicle engine driven belt powered OBA system
Each system has pros and cons, so without further delay lets take a look at each OBA system.
First, the CO2 powered On Board Air system (sometimes compared to a scuba tank for it’s similar look). This OBA system was developed 15 years ago and airs up tires in the fastest times using highly compressed CO2. Powertank (www.powertank.com) is the originator of a system that can be carried easily yet offers the ability to operate air tools. CO2 systems are a good choice for those four wheelers who run large tires (35” and larger), plan on running air tools or are just getting started in the sport but are looking for the OBA system that can do it all. CO2 systems can be mounted on your 4x4 almost anywhere they can fit (even outside) and come in many different sizes to suit everyone’s needs. This style of OBA system is favoured because of its speed in airing up tires – similar to good gas station air compressor. The only con to this system is the need to replenish the CO2 once it’s depleted. The charge for doing so is minimal at about $10 or so for one tank and obviously the amount of use dictates the need for refills. The average weekend four wheeler using this system to air up tires would need a refill once or twice a year.
The basic 12-volt electric powered air compressor is the more common system on the trails today. There are many companies manufacturing this style of OBA, making it a very affordable system. They range from the very, very slow models found in Big Box stores to premium models that are capable of airing up tires in a reasonable amount of time. The ability to reseat a tires bead is possible with the premium models of electric OBA systems, albeit some wrestling with the tire carcass may be needed. As these electric OBA systems require a strong 12-volt source many are mounted under the hood and wired directly to the battery. Portability is possible (from vehicle to vehicle) but a strong 12-volt battery must always be available for operation. However unless a premium unit is selected, the con to these systems is the lack of speed (best used for tires 33” and under) in airing up and the inability to run air tools. Yet they do make for a reliable system if kept from running to long at one time.
Last up is an old stand by, the vehicle engine belt driven air compressor similar to how a power steering pump or alternator is turned by an accessory belt. Essentially a small compressor is set up on the front belt drive of the engine allowing the belt to spin up the unit and produce a good air source for airing up tires and reseating tire beads. Check out the Air Boss kits using York compressors from Kilby Enterprises (www.kilbyenterprises.com). An engine driven OBA system is more than capable of running air tools when operated with an air tank for storage, allowing the use of air tools for extended periods. This system, while about three times more costly then the premium versions of the other two systems on the market, has the ability to offer endless air at very good volume as long as the vehicles engine is running. The con to this unit, other then the systems price, is that portability is limited to where you can drive the vehicle. This might not seem bad at camp, but during many on-trail occurrences that require an OBA system, the trail is usually difficult to severe, offering little if any opportunity for a second vehicle to get close.
Finally, OBA offers more then just the capability of inflating flat tires or reseating a tire bead, how about a nice cold air powered blender drink back at camp after a day on the trail. Ideas like that can really make an OBA system priceless in the backcountry. The need for air tools can become very appealing to 4x4 operators who like to push the limits of their machines capabilities along with their trail repair capabilities. Only air tools can complete some of the more severe trail carnage repairs, allowing off-roaders the confidence to tackle tough terrain knowing that extreme breakage can still be repaired on the trail. The ability to manage these situations while many km’s from the nearest air source is essential to getting home safely - and when expected.
OBA is an essential piece of equipment for the avid off-roader and before deciding on the right system and plunking down your hard earned cash, ask yourself how you intend to use an OBA system. Does the system need to be portable? Is accessing a refill station going to be a problem (CO2 is required for a refill, so you need access to a fire extinguisher store or welding supply shop)? Will it be very difficult installing a belt driven compressor under the hood of your 4x4 or finding a suitable place for an air tank?