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Having an on-board source of compressed air is SUPER handy for more purposes than you can even think of before you do it. The W460 G-wagen really lends itself to a lot of choices for on board air. This article covers fitting a York air compressor right where the factory AC compressor goes.

The G-wagen is very well suited to most any task, just as it rolls off the showroom floor. But if you use your G in extreme conditions that require the utmost traction, one of the best modifications you can make to enhance safety and convenience is an on board air supply system. There are many ways to go. If you live in a climate where you just can't give up your air conditioning system, or if you have a factory AC system that's still in good condition and you want to maintain it in place for potential resale value, then the best option for you is probably a Power Tank system. They're simple, portable, and self-contained. And another big advantage is you can keep the system when you sell the vehicle because installing it means very little modification to the vehicle. For a lot of great information on Power Tank installation and parts, visit my friend John at Expedition Exchange

In my case, the AC system that was in my truck was not working and here at 9,000 ft. in the rockies I don't need AC anyway. So, I opted to replace the factory AC compressor with a high volume, high pressure York compressor. The main advantages of this system are that its always there, tucked away totally out of sight and out of mind under the hood, and always ready to perform whenever needed. Maintenance is minimal, only requiring a periodic check of the oil level and emptying the water separator in the output line. I don't have to anticipate a need and remember to load a tank on board, or sacrifice any space to that tank. The former is by far the greater issue to me. Quietly being always prepared for any eventuality. Isn't that what the G is all about? :^)

(1) This is the York compressor I used. It was given to me along with the truck by the previous owner. Compressors like this one and all the parts you need for a first class installation are available from Brad Kilby at Kilby Enterprises. Brad is a first class guy who knows how to take care of his customers' needs. But, like any small businessman with a great product backed with excellent service, he's very busy and difficult to get in touch with personally, so take the opportunity to deal with his excellent and knowledgable staff whenever possible.

In the background of the previous picture, you can see my old stock compressor. I could actually have used this one with no problems, since if you check out Brad's guide to York compressors, you'll see that the unit fitted to the G is the most desirable high pressure unit. But, I wanted to keep the old AC system intact in case someone else might need or want it some day, so all I took from the old system was the magnetic clutch actuator, pulley, and clutch. If you don't have AC on your rig, all of these parts are available from Kilby Enterprises. But if you already have an AC system in place, you have a cheap and easy way out by just using your current compressor setup already mounted on the engine (once you have the freon evacuated from the system by a licensed AC shop and the hoses removed from the compressor). The York compressor is superior to other AC compressors for this application because it has it's own oil supply in the crank case and does not depend on oil in the freon system to lubricate the compressor. Most other AC compressors require oil to be drawn into the inlet side of the pumping cylinders to be properly lubricated and avoid seizing or wearing out. This makes them difficult to adapt to on board air systems due to the need to maintain the recirculating oil supply and filter the oil out of the outlet air so you're not filling your tires with oil mist as you air up. The York has no such difficulties though since the oil is kept in the crankcase, just like your car's engine and all lubrication is internal to the compressor, not in the air lines. Maintenance is confined to opening the hex bolt shown on the side of the compressor and using the special dip stick and instructions from Kilby to verify proper oil level. I check the oil in the compressor at every engine oil change and haven't had to add any in 6 months. At the same time I drain the coalescing filter in the air line to remove any water that's been separated from the outlet air during operation (a byproduct of compressing the air).

(2) With the compressor in place on the engine using the factory G-wagen mounting brackets, it's just a matter of plumbing it in with some copper pipe fittings available at the local hardware store, and a few specialized components available from Kilby. Or, if you're into one-stop-shopping, Brad offers all the fittings and components you'll need right on his easy to navigate web site. Inlet Filter - replaceable element Fittings and flex line Check valve Coalescing filter - moisture trap Auto shutoff pressure switch (on at 90, off at 120 psi) Pressure relief safety valve (opens at 150 psi) Line to in-cab pressure gauge Outlet line to air tank Inlet and outlet fittings to adapt compressor to pipe fittings

(3) I used the right hand side rock slider as the air tank on my truck. Some type of small tank is necessary so you're not asking the compressor to turn on and off every time you ask for a bit of air. The tank will keep a small supply on hand (enough to air a couple good sized tires up from 20 to 32 psi) and allow the compressor to cycle on and off less frequently, saving wear and tear on the compressor clutch. A simple tee fitting allows the line from the compressor, the air tank, and the outlet quick disconnect fitting to all be located in the same convenient place, just below the passenger side front door. From here, a high quality coiled hose (I actually use a Power Tank hose from Expedition Exchange) can reach any point on the vehicle, and even trailer tires at a stretch. A second hose would be a good thing to keep on hand for extra range. When you see how fast this system airs up tires, (1 psi per second), you won't want to wait around for others, and will want to be able to reach their tires to help air them up too! The system also provides plenty of volume to run air tools even with the engine just at an 800 RPM idle. The outlet fitting in this picture is covered by a 35mm film canister. I cut a small hole in the canister's lid and fit it into place before threading on the quick disconnect. The lid always stays in place and the canister can be snapped off for full access to the fitting. I've used the system in the dead of winter when I had to kick ice and snow from around the canister, but once the canister was removed, the QD fitting was waiting inside, clean and dry and ready for use.

(4) This is a picture of my dash board. The amber switch on the right takes power from the fuse panel (switched on by the ignition key) and when in the on position, supplies power to the pressure switch under the hood. The pressure switch supplies power to the compressor's pulley clutch, engaging the compressor, as long as air pressure is below 120 psi. When the compressor has pumped the tank up to 120 psi the pressure switch interrupts power to the compressor clutch until pressure drops below 90 psi, when the pressure switch re-activates the compressor clutch to raise air pressure again. Just above the switch is the pressure monitoring gauge. This is just a geek thing, admittedly. There's need for the gauge, and the extra plumbing is just more opportunities for leaks. But, I like the way it looks there on the dash, and somehow feel more in control when I know how the system is operating.

To give an idea how easy this system is to use, the other day I had no pressure in the tank and needed to increase the air pressure in my tires after negotiating some deep snow. I stopped at the road side with engine idling and flipped on the compressor switch. By the time I got the air hose out from under the seat, kicked the ice off of the quick disconnect cover, removed it and snapped the hose into place, I heard the compressor shut off at 120 psi. I then inflated all 4 tires from 25 to 32 psi, exactly 7 seconds each. It actually took more time to remove and replace the valve stem cap on each tire with my gloved hands than it did to inflate the tire. I got the air hose removed, cover replaced, and the hose and my tire pressure gauge stowed away, all in less time than it takes to fill up with gas. At that point I was again set up to safely negotiate the twisty paved roads that lay ahead. LIke I said, I think the on board compressor system fits in nicely with the rest of my G's personality. Always ready to tackle the task and conditions presented with minimal compromise and maximum effectiveness. If your truck doesn't have AC, you can Click Here to e-mail me for a list of the MB brackets and pulleys you'll need to mount the compressor. You'll have to send me the Vehicle Identification Number of your truck though, since the parts are specific to individual engine types. 230G and 230GE models use rotary or axial type compressors and can not fit the vertical York Compressor using factory parts. I'm not certain about other models, but I do know that the 280GE uses the vertical York as shown here and it can be fitted using factory bracketry.

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