Review: ARB Twin Air Compressor

Nov. 12, 2012 By Jaime Hernandez
Air up, air down—something done almost every time we hit the trail. Having a good air supply to fill those tires is not only important, but it is necessary to safely get to and from the trail. From setting air pressure for different off-road terrain to filling tires for highway travel, air is what keeps the wheels rolling.

Up until recently, we’ve been relying on gas stations and a small portable air compressor to air up. Ready to make the jump into a more powerful on-board compressor, we set out to find the best air solution for our adventure rig.

Hugh Pinto from Safari Ltd. was nice enough to show us his ARB air compressor while in Moab. His on-board setup and real-world advice is what crystalized the idea of us getting an on-board setup for our rig.

After searching for a few months and looking at different options, we chose an on-board compressor from ARB. Originally designed for use with ARB Air Lockers, the compact electric compressor line has proven to also work well for airing tires. In fact, there are many people that don’t have air lockers but still own an ARB air compressor because of its reliability and performance. 

Looking closer at ARB’s air compressors, we learned about their latest twin motor model called the CKMTA12.

ARB’s TWIN
The new ARB CKMTA12 Maximum Performance Air Supply has the highest air flow rate of any 12V compressor of its size on the market at 6.16 CFM.

ARB’s new Compact Twin Compressor CKMTA12 model offers the best of both worlds—high airflow power in a small package. This 100% duty-cycle, 6.16 CFM compressor is built to support your rig on and off the trail. It can activate ARB Air Locking Differentials, air up a 35-inch tire in less than a minute and run air tools.

Some of the key features are highlighted below.

The ARB CKMTA12 is constructed primarily of lightweight, high-strength, engineering grade materials, including military and aerospace standard components. The compressor measures 4"(H) x 7.5" (L) x 10.8" (W) and weighs 19.4 lbs.

It is powered by two-ducted IP55 sealed brushed DC motors. What's unique on this model is the cooling fan is a brushless design that makes it more efficient at effectively dissipating heat from the motors, heads and electronics allowing for a 100% duty cycle at 72°F.

There are sealed components for moisture and dust resistance. Hard-anodized cylinder bores and PTFE (Teflon) impregnated carbon-fiber piston seals for reduced friction and maximum trouble-free life. It also features Built-in Thermal Overload Protection to ensure the components don’t get damaged under extreme use.

The built-in mounting plate has eight mounting nuts for installation flexibility, though only four need to be used. To make sure the twins stay harmonious, anti-vibration and sound deadening is integrated into the mount.

Another nice feature are the two relocatable, splash-resistant air filters. They have washable high-flow sintered bronze filter cartridges. Both filter housings have the ARB logo molded on them.

The CKMTA12 is a big improvement over smaller ARB air compressor models and perfect for those looking for a multi-use compressor.  It fits our need, so we ordered one.

AIR ACCESSORIES

We also acquired the ARB “Pump Up Kit” along with the compressor, which includes a 20-foot high-temperature air hose, ARB push-lock quick connect hose coupling, T-connector piece and inflation accessory kit. This kit is recommended for use on ARB air compressors and can be used for applications with or without ARB Air Lockers.

Also available is the ARB Forged Aluminum 1-Gallon tank, designed to work with the CKMTA12. The additional air capacity of the tank allows the twin compressor to properly supply higher PSI power air tools. We didn’t get a tank yet, but it’s on our wish list.

ADDING ON-BOARD AIR COMPRESSOR

 
One of the most important questions when adding an on-board compressor is deciding where to mount it. For an electric-powered model like our ARB compressor, you want to place it as close to the battery as possible. It should also be in a spot that is easily accessible and will not be exposed to mud, dirt, water or heat. Compressors work best with a cool air source and out of harms way.

For those looking to mount the compressor in a spot that requires extending the power lines, keep in mind that the longer the power line the more resistance--which equals less air flow. Voltage actually drops with each foot of wire added between the battery power source and the compressor motor. It can be done but it needs to be correctly wired.

The ARB CKMTA12 comes with a complete wiring loom with Air Locker solenoid plug-in terminals and OEM quality compressor isolating switch. It also includes dual 40amp/32v fuses.

If you stick with the ARB wiring loom, you’ll be good. It’s roughly three feet long. If you need to extend it, then make sure to run larger diameter wire to compensate for the voltage drop.

To learn more about different wire gauge and current limits, make sure to check out this resource we found at http://www.powerstream.com/Wire_Size.htm.

We placed our ARB Twin Air Compressor in the rear cargo area. It has plenty of room, is protected from the elements and it also makes routing the air hose through the side utility windows on our Land Cruiser functional. We have big plans for this section of the vehicle, and it made sense to keep our air compressor close to our tools and recovery gear.

The complete installation for the ARB CKMTA12 Twin Air Compressor takes a few hours to do and requires electrical wiring, drilling, fastening and plumbing. It also requires knowledge in the areas of automotive mechanical and electrical to properly install. ARB does include a very well documented, 24-page installation manual that simplifies things, but even then they do recommend the installation be done by a professional. 

FINAL THOUGHTS
ARB on-board compressors are one of the best on the market. Having the ARB Compressor switch on our instrument panel brings a big smile with a cool blue light. Rock that baby and the twins come alive!

Overall, we are really pleased with the new ARB CKMTA12 air compressor. It has a very striking design, and packs a lot of punch in a small package. The product seems very sound in construction and works as advertised by the manufacturer. It does in fact fill tires quickly, much faster than other electric compressors we’ve seen on the trail.  In our experience 33s are a breeze, 35s no problem. Although 37s and 40s are certainly do-able, they will take a little longer to inflate.

As for air tools, powering a 1/2-inch impact gun can be done. Having the auxiliary ARB 1-gallon tank is highly recommended for those looking for the pit row experience as well as pumping up 40-inch tires.

In the future, we plan to add the auxiliary 1-gallon tank to help create an even larger supply of air so we can quickly fill our tires and help others in need. The added PSI and air supply will also work well for even more pneumatic power tool options.

The only bad thing we found, if it’s even considered bad, is that the CKMTA12 is much larger than the smaller ARB air compressor models. For those looking to mount in the engine bay or a small nook in your vehicle--think again.  The CKMTA12 takes a good amount of room, so plan accordingly.

We’ve seen people successfully mount them under rear passenger seats, on top of the wheel well inside a Jeep, and Slee Off-Road notes installing the ARB CKMTA12 in a drawer cargo system. It just takes some imagination and the ability to make it work for you.

If commitment to an on-board air system is an issue, then may we suggest the portable CKMTP12 Twin Air Compressor from ARB.  It’s the same compressor as the CKMTA12, but it comes with its very own case and auxiliary 1-gallon tank.  This model hooks up directly to the vehicle’s battery and can be transported with ease.

Either way, make sure you have a good source of compressed air for your off-road vehicle. It will make your trips more enjoyable and safe. 

SOURCE
ARB 4x4 Accessories
(425) 264 1391
http://www.arbusa.com/

Safari Ltd
(970) 245.5898
http://www.safari-ltd.com/

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