View Full Version : On-board electric air compressors

07-23-2010, 05:37 PM
I was planning to install on-board air in my 80, and had most of the big parts purchased, but then switched gears and installed a supercharger.

I used to have a CO2 tank in the back, but since I installed drawers I don't have anywhere to mount it.

So now I am thinking about purchasing one of these new, high output electric compressors.

Brian Wilson has this ExtremeAire compressor (http://www.extremeoutback.com/index.cgi?cart_id=5652890.12879&pid=30), which looks really good.

Viair has so many products (http://www.viaircorp.com/OffRoad/products.html) that it's impossible to determine which one a person might want to buy, and they don't list any pricing on their website.

Any others to consider? Anyone have experience with any of these?

07-23-2010, 05:54 PM

I have a Viair portable unit. I'd have to look to see which one I have but I think it is the 440P.

It has been great and will air up my 285s from 18psi to 42psi in about 4 mins per tire. Not stellar fast but fast enough for me.

The only negatives I have are that the included psi gauge is not very accurate when the unit is operating (reads 4-6psi high IIRC) and that the unit gets VERY hot.

I just adjust how high to go (i.e. shoot for like 46psi in the tires to end up at 42psi) when relying on the gauge rather than turning the unit off and on. For the heat, I try to let it cool off before packing it all back up in the bag if possible. If I'm in a hurry I leave it sitting free, away from other items, in the back during the drive home. Sometimes a challenge if you have a bunch of crap in the back.

An important thing to consider is the duty cycle...You don't want the compressor overheating and shutting off 1/2 way through filling up your tires. I bought bigger than needed to avoid that and also so that if others needed to borrow the compressor they could without having to wait for it to cool down.

07-23-2010, 05:59 PM
Perhaps Red Chili will chime in. IRRC, he has the Extreme Air, or something very similar, on his mini. I think he may have two, but I could be wrong.

Something else I've seen done Matt, if you have room for it, is the 4 tire hook ups, such as the one 4crawler has, which makes the air compressor slowness almost a cool thing, as you can sit and BS for a while without having to check and move the compressor constantly. Essentially, hook it up, and walk away. Time it once at home, and just watch your watch (clever :D) while talking with buddies, then go shut it down at the appropriate time. Also has the added benefit of getting all 4 tires to the exact same pressure every time.


07-23-2010, 06:15 PM
So that's why my ears were tingling. ... :lmao:

I have a pair of the Checker cheapies that I love. Two gives me more speed as well as redundancy. They can be gotten at Amazon and Pep Boys IIRC but not for the 25 that I paid.

I have had two failures. One was the internal relay which I did not need anyway. I use external 40A units. The other was a thrown rod (the retainer didn't retain). I have abused them for years and love them.

Dr. Schlegs
07-23-2010, 06:38 PM

07-23-2010, 10:45 PM
I have a Quick Air 3. It was given to me a few years back and I think it was several hundred dollars. I has a horrible duty cycle and has crapped out twice on me, last on the BOWR. I really don't have faith in anty thing electric that is considered affordable.

07-24-2010, 06:46 AM
I have the same Viair 440P that Corsair has and have the same complaint regarding the gauge. Other than that it has worked great and is really easy to bounce between vehicles if needed.

07-24-2010, 06:52 AM
I took the style that bill has and mated it to a HF twin tank unit, and bolted that to the shelf unit. worked the treat. It was at cm07 right before I sold the 80.

Worked great for tailgate margarita parties, blowing the dust out of the truck, oh and air tools.

CO Hunter
07-24-2010, 08:41 AM
I got the MV50 from Amazon for about $55 shipped. I read a bit about it on MUD and for a cheap compressor folks seemed to like it. I've used it a few times and it inflates my 285's from the teens to 40 psi in about 4 min for each tire. The last outing it did seem to slow a bit on the last tire. So far so good.

07-24-2010, 12:18 PM
I have the viair 400? and cant say the good things the others have. Used 3 times.First very good 2nd intermitantly 3rd nothing. All 3 times were flat repairs on my car so it was not abused or overheated or any thing like that.
Not a very good investment for me! If anyone is interested in trying to repair get ahold of me and you can pick up or I may drop off,I live in Denver and work in Commerce City. If you can get it to work for you you owe me a beer if not you get to dispose of it.

Uncle Ben
07-24-2010, 12:48 PM
I had the Extreme Air on Long Grain and it worked pretty good. I had it plumbed into both sliders for air storage. Key to any compressor is storage. Electric comps are always a disappointment compared to belt driven or even CO2! Duty Cycle is everything when comparing elec vs elec. Also, buy the biggest you can get to fit! Matt, since you already have CO2 why not mount it on your spare tire swing out?

Air Randy
07-25-2010, 10:32 AM

I have on board air on all 3 rigs. On the Mule and the Gecko I used the ARB HD compressor rated for tire inflation as well as locker operation. I also used a ViAir 2.5 storage tank with each of them. These compressors have a 50% duty cycle which means they can run non-stop for 30 minutes and then they must cool off for 30 minutes. They are sealed so they can be installed in the engine compartment and they come with pressure sensing shut off switches, etc so they fill the tank to 90 psi then shut off. You can also plumb the air intake to the inside of the vehicle to ensure clean air going in to the compressor. The Mule has 37's and the Gecko has 39's which I usually run down around 2 psi with the beadlocks. The ARB compressor with the air tank will fill all 4 to 20 psi in less than 30 minutes, so I have never had the duty cycle become an issue.

On the Meanie it came with a ViAir 450C and 1 gal tank. The 450C is rated for 100% duty cycle and will go up to 150 psi.

I don't think you can go wrong with a ViAir unit. I get my stuff like that from 4 Wheel parts, they seem to have good prices. If you only use it very occassionally and for light use one of the HF units might be OK.

If you want faster fill ups get a compressor and air tank rated for 200 psi, then put an adjustable regulator on the output. If you are operating air lockers you can't go over 90 psi or it can blow out the locker seals.

Which every way you go I agree with UB and suggest you get a storage tank. Even on the Meanie with a 1 gal tank, you can operate the air lockers all day long and never have the compressor kick on.

07-25-2010, 10:27 PM
I have had my Quick Air II since the late 90's. A champ. Coupled with the 5 gal tank charged to 100 PSI it does the job.

07-25-2010, 11:46 PM
I've also got a pair of the Red Chili Checker cheapies... with dual batteries you can run one off of each battery to double up. They work ok enough, but if everyone else has OBA and CO2 you'll be the last guy filling up for sure, but park next to them and they'll probably do a tire for you. :hill:

IMO don't hard mount it, your engine bay is hot and heat is the enemy.. plus you could toss it in the 40 as backup just in case your CO2 runs out again... I'll toss one of mine in the 80 just in case of OBA failure.