I'm debating over the Extremeair portable and the hardmount unit. If I get the hardmount unit, what all would I need to mount the compressor under the hood and use my rear bumper (2"x4" tubing) or sliders (2"x3" tubing) as air tanks? Air lines, presure switches, etc? I need an OBA education here.

 

I have an on-board air system. As far as mouting under the hood I can help you, but I do use my sliders as air tanks. For the basic setup you will at least need a pressure switch, relay, switch for inside the vehicle, air line to run from the compressor to the bumpers and sliders, tap set to tap the bumpers and sliders for an adapter of your choice. And may misc. fittings.

Word of advise, if your sliders and bumper weren't made to hold air they probably won't. Although most welds look solid there tends to be many tiny holes that will leak enough air to screw-up the system. I would recommend taping your sliders and bumper and put a typical tire valve type fitting in. Fill them up to 110-120 psi or wherever psi you plan to use and see if they will hold before you mess with running lines.

 

Good idea about seeing if they hold air. Got a writeup on your setup?

 

No I don't. I would like make one someday when I get some more time.

 

Keep in mind that unless you install a filter/separator, you will be pumping water into your sliders/bumpers as well. I know mine are not painted or otherwise sealed inside.
Personally, I would buy a small airtank and mount that behind my TJM.
Mike

 

Good point, I guess you could also install a drain cock. I really don't see much use for a little compressed air though. What, maybe you could fill 1/2 of a tire with it?

 

??? Are you thinking that you would only load your tires from the stored air? Most any OBA system that you go with has plenty of capacity to fill tires straight from the compressor, it'll just be slower than filling them from a reservoir loaded to 120psi.

fwiw, I can load my 32"(ish) tires from 15->42psi in about 4 minutes from my Viair 450c. The ExtremeAire will do the same task in under 2 minutes.

 

Here's what I have for tires: http://community.webshots.com/photo/...63081887CFnVVk

 

Yeup, CO2 is a valid option as well.

Pluses and minuses on both sides... Dragr1, you gotta decide what makes the most sense for you.

 

Seems the simplest is just to buy the Extremeair portable, I can even use it in my work truck then. Less air lines to get holes, no water in the sliders and bumper, etc, portable seems best in my case.

 

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So do you not have a tank with your Viar compressor? I just picked up the same compressor, and I was debating on getting a tank or not.

 

unless you get a moderately large tank, there is no real advantage to having one. The only reason I'd consider one is to run an impact wrench. That's one of the reasons I went with CO2. The other is speed- the CO2 tank is like using a very large shop compressor.

 

What do you consider moderately large? For now, it'll strictly be for airing my tires up and down. In a few years, I'll have an arb in the rear, so I'll most definitely be getting a tank then.

 

Well, I do have a small 2 litre tank (you can see it in the thread that sdastg1 pointed to above) but it's only there for supporting my air horns. When I air up, the tank is depleted _very_ quickly.

If you're not going to run a tank (or even if you do!) then do yourself a favor and spend the extra money on a compressor that has a 100% duty cycle. Viair makes a couple of different flavors of their compressors... One side of the line has a 100% duty cycle (the "c" in "450c" is for "constant use") and the other side of the line has only a 20% duty cycle. Low duty cycle compressors _will_ let you down on the trail!

 

I've got the 450c. I picked it up a couple weeks ago. I've just been debating on getting a tank or not. Running tools and a locker on it will not happen for another few years, so I was debating on just waiting on the tank. The main purpose for now will be airing up.

 

'k, then I'd say that you don't need a tank. Any tank that you put on the truck that has enough capacity to run air tools for a while will basically fill the back end of your rig. The 450C doesn't push enough air on it's own to run a tool, so it'll all have to come from a tank.

That's where a CO2 setup really shines - you can run tools right off of the tank.

 

According to Power Tank's web site http://www.powertank.com/chart.htm , a 5 gallon tank @ 90 PSI, 4.5 CFM flow should be sufficient to run a 3/8" impact wrench for a short time- prolly about 6 seconds at a time. Seems like a pretty short time, but your compressor will be refilling it too. If you think about how long you actually run an impact wrench on stuff like a lug nut, that's enough time to hit 5 or 6 before it's depleted. It would also be excellent for an ARB- overkill, but.......

The other application I forgot about is reseating tire beads- that takes a LOT of volume. I've used my CO2 system twice for my own tires and several times for other rigs. I use a wrachet strap to snug the tire up to the rim, and a can of foaming window cleaner to slick up the bead- works like a champ.

 

So, if I don't run a tank, what accessories would I need to hook it up? I'm guessing just a relay and a switch.

 

Electrically, you can certainly do it with only a switch triggering a relay that's switching power to the compressor.

On the air side, you have some more purchases to make.. .

Given that you're in Humidville USA, I' REALLY suggest running a watertrap. If you don't, you're basically pumping water into your tires. You can get them for under $20 (don't forget the mounting ring!) at a Home Depot or Lowe's.

You'll also want a good air gauge, a "_OPEN_ locking tire chuck" (*see below), and pick up a couple of those coiled yellow air hoses when you get your watertrap. You'll need miscellaneous air fittings and the quick disconnects for the ends as well.

And, you may want an easy-to-get-to accessory tap mounted on the bumper for the air. That's generally just a piece of 1/4" steel bent up and drilled to accept a quick disconnect fitting. That'll stay there all the time, then when you need air, flip the switch in the cab, and plug into the fitting.

Now, to make it easier on you... You can run a manifold on the compressor, then attach a pressure switch into one port and your air hose into another. The pressure switch gets wired such that it kills the power to the compressor when the pressure comes up to 120psi or so. With the quick disco on the bumper, that will let you just plug in to the disco with your air line and the compressor will start. When you disconnect the line, the disco fitting will block the airflow, the pressure will come up, trigger the pressure switch and the compressor will shut down.


* - you need the open chuck in order to protect the compressor. If you run a closed chuck (i.e., no air flow unless it's on the tire) then the compressor will keep running and something going to give. If you run a pressure switch, then you can run an closed chuck.


Have fun!