Educate me about air compressors

[buchaja]

I've got a small Craftsman compressor I bought thinking it would be sufficient to air up my tires. It sucks. I can usually get the 32psi tires on my 4runner done with one or two cycles per tire, but my truck's 35psi tires wear me out filling them.

So, what am I missing? Do I need 900 bazillion psi to quickly fill tires? Is CFM a more important rating?

Seriously, help please. I am going to get a replacement for the Craftsman, but what should I be looking at?

Thanks :hatsoff:

 

[having fun]

First thing is always CFM. Look at air tools ratings, that will give you an idea of volume it takes to run tools' let alone filling tires.

Second, the tank size is how much volume of air that can be stored before pump has to engage.


Third, your pump, how many cylinders ( some consider lungs ) it has to develop the air in your tank. more cylinders, the quicker it fills the tank.

Fourth, Duty cycles on the electric motor to drive your pump.

If your really looking for air, you need a 220V.


I shopped on CL for almost a year to get the one I got, and was worth the wait.
Pick up a Campbell Hausfeld 60 gal, 7 hp continues duty motor w/ 4 lung pump. I think it's rated 18.3 cfm @90 psi, 16.8 cfm @ 135 psi. A steal for $450. 1996 model.

 

[Jeremy556]

Are you asking about shop/garage AC powered compressors, or 12v compressors?

 

[BucknutBob]

While the conversation so far has been about home compressors, I would assume that since you mentioned airing up tires, you're talking about portable air compressors for the trail. The most important thing to consider is definitely volume, not pressure--you can find $20 compressors at dollar stores that put out 200 psi, but they'll take a year to air up your tires. You want something above 3 cfm for big tires. Yes, you'll pay more, too. Duty cycles is very important, also--that tells you how long it can run before overheating. 100% is best, as it never has to shut off, but something with a fairly long minute count is still good. An auxiliary tank of a couple gallons helps out a lot, so you can store some compressed air for larger jobs, cutting down on how long you need to run the compressor. You'll be in the $300-600 range for a quality unit that you can either carry along or permanently mount on your rig.

 

[RiFF RaFF]

I'll keep this short - Viair onboard system is THE way to go.

:guitar3:

 

[1blink]

For an occasional use portable compressor, look up the MV-50. Best bang for the buck.

 

[Canazes9]

For an occasional use portable compressor, look up the MV-50. Best bang for the buck.

Agreed! I have absolutely no regrets about purchasing my much more expensive ViAir 450P - its a quality unit, works awesome. Purchased a MV-50 as a "just in case" back-up and have been very impressed. High quality compressor for the dollars, available at most auto parts stores.

An old review:

air compressor test

Keep in mind those prices were from 2005 - I have never seen one for sale at $49, but you can buy at all day long for $79 and that's still cheap for a decent air pump.

David

 

[cbielat]

I too have a Viair 450P. It's a great compressor to have. Check one out.

 

[TexasAg]

I have the Warn VTC (Vee Twin Compressor). This sucker puts out enough volume to run an impact gun (8cfm @ 90psi) and has a 1 gallon built in tank. I put an Anderson high amp connector on one end and the battery on the other. Going to install a high amp in the back too.

 

[kenski]

I don't think craftsman makes a portable air compressor so I think the OP was talking about a shop compressor. But I'll let the OP clarify.

 

[Limbwalker]

I also have an MV50. It does a pretty good job for the money, and could be hooked up to a tank for more volume.

Q Industries MV50 SuperFlow High-Volume 12-Volt Air Compressor : Amazon.com : Automotive

 

[buchaja]

I was talking about my home shop compressor, but you guys can take this thread any direction you want. I've been curious about 12v units too.

I see now it's the CFM rating that's killing me when I'm airing up my tires. I think the Craftsman is rated around 3.8 or so.

Once again, thanks for all the replies. This forum rocks! :guitar3:

 

[jwyshrek]

So what are the specs on your current air compressor? Is it something like this...see pic below.

That's what I started out with (except it had a Coleman name on it)...ok for car tires, but on the 4runner, it probably would burn itself out airing up just one tire.

Then I got a 10gal, 1.5hp, 150psi max oil-less unit...no problems. Don't remember CFM or have a picture (sorry).

(yeah, yeah, I hear you guys out there...oil-less unit don't last as long as oil-ed units...true, but I also heard that if you don't have a filter on your oil-ed compressor, the oil from the compressor could damage your TPMS. I never confirmed this, just heard about it...)

 

[Jeremy556]

Another reason for oiled compressors is noise. I can have a conversation while producing 5 CFM at 90PSI.

 

[buchaja]

So what are the specs on your current air compressor? Is it something like this...see pic below.

That's what I started out with (except it had a Coleman name on it)...ok for car tires, but on the 4runner, it probably would burn itself out airing up just one tire.

Then I got a 10gal, 1.5hp, 150psi max oil-less unit...no problems. Don't remember CFM or have a picture (sorry).

(yeah, yeah, I hear you guys out there...oil-less unit don't last as long as oil-ed units...true, but I also heard that if you don't have a filter on your oil-ed compressor, the oil from the compressor could damage your TPMS. I never confirmed this, just heard about it...)

Mine is a 3 gallon, 1.5hp max/1.0hp running, and here's where I think it's killing me: 2.4 SCFM at 90 psi. (I was a little optimistic in my previous post.)

It's oiled, and I never even though about the TPMS - this is my first vehicle with that. But, I can confirm it works. The warning light came on the other day, and sure enough, two of my tires were real low. I used the opportunity to air up all the tires on my 4runner and my F150.

I need a better compressor! That 12v posted above from Amazon looks interesting. Thank to 1blink and Limbwalker for posting that link.

 

[buchaja]

Another reason for oiled compressors is noise. I can have a conversation while producing 5 CFM at 90PSI.

First thing I do before getting out the Craftsman is put in hearing plugs. My hearing is about half gone anyway, so I'm just trying to protect what's left.

I'm guessing my little Sears unit is noisier than yours. 5CFM sure sounds nice.

 

[Jeremy556]

FREE SHIPPING — Ingersoll Rand Garage Mate Air Compressor — 2 HP, 5.2 CFM, Model# P1.5IU-A9 | 2 - 9 CFM Air Compressors| Northern Tool + Equipment
I have an older model of that compressor -largest that will run on 115v 20 amp outlet, and is semi portable. I put in a filter and a long U shape piece of iron pipe with a drain at the bottom to catch some of the moisture.

The MV-50 compressors are OK, at best. If you get one that works out of the box, it won't last long with often use. I went through several of them. They look like a Viair on the outside, but the materials and tolerances are completely different.

 

[jrandom]

The MV-50 compressors are OK, at best... ...They look like a Viair on the outside, but the materials and tolerances are completely different.

I had to post in on this too, I have an MV-50 of which I spent about an extra $50 modding it out, had I known what a piece of shit the head was I would have thrown that $110 towards a better compressor. I read a ton of things about how great this thing is, while it is a pretty good little compressor for the price, the cast aluminum head is garbage.

Anyway I dug this thread up looking for portable 12v compressor opinions, I was hoping to see more of specific Viair Constant Duty and ARB's twin compressor as those happen to be the models on my radar. If anyone has either I would love to hear about your experiences mounting/using/ect.

 

[Jeremy556]

Anyway I dug this thread up looking for portable 12v compressor opinions, I was hoping to see more of specific Viair Constant Duty and ARB's twin compressor as those happen to be the models on my radar. If anyone has either I would love to hear about your experiences mounting/using/ect.

If I had it to do over, I would definately get the ARB twin compressor. I have dual Viair 400s (highest CFM that Viair had available) now which have similar performance to the ARB, but using much more space and a higher cost.

The 400s are only 33% duty cycle, but even when I was running only one, in the engine compartment, in the desert, it never had a thermal shutdown. The dual 400s fill my 285/70/17s from 12 to 37 psi in about 70-75 seconds per tire.

 

[jrandom]

Ah good to know thanks The numbers always look good on paper but I find experience to be much more valuable.

I like the compactness of the ARB twin but the price is certainly on the high side, it is really the only limiting factor.