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I am going to do this on my Legacy- with the stock A/C compressor...

 

I will take lots of photos, and do a full write up of how it's done, when it's done.....

 

 

My opinions on why you should use the A/C compressor over the electric ones-

 

1) you probably already have an A/C compressor on your car, and if the car is as old and beat as most of the ones I see on the forum, it probably does not blow cold air anyway.

 

2) it already has all the "connections" it needs to run off your engine- provided your belt is still there, and you have enough wire to connect the 12v signal to engage the clutch...

 

3) it can probably be used almost continuously (as long as it's lubed) and it wont have overheating troubles....

 

4) volume of air... (as stated earlier in the thread) to inflate either a flat, or 4 aired down tires is much quicker and easier if you have your car just idling and an onboard air tank already full (from when you were driving and compressing)

 

5) (most importantly) its cool :cool:

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Sorry to dig up an old thread, but I'm working on this project as well. My 86 GLW came with an EJ22 swapped in, and the AC was disconnected but the PO did give me the EJ22 compressor. Gonna grab an oiler and filter setup from harbor freight, and am gonna try to use the giant 4x6" tube I installed for a rear bumper as an air tank. Looks like the hardest part is simply converting the plumbing from the compressor to some usable pipe threads.

 

Another silly idea I just had was to attach the input of the compressor to my engine's PCV system. It'd kind of work as a crankcase evac system, and my blowby would be captured by the oil seperator downstream from the compressor.

 

I've been digging around on the Intarwebs, and nobody has put together a properly comprehensive guide to doing this, so once I've got the parts I'll see if I can do a little writeup.

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Do EJ's use Sanden compressors? If they do its super easy and doesn't require an inline oiler, like a York, but you shoulds always run a oil seperator.

 

Heres some links for Sanden Compressors I've accumulated over the years, most of it is Jeep related, but a Sanden is a Sanden:

 

http://www.cherokeeforum.com/f2/c-onboard-air-compressor-21871/

http://www.cherokeeforum.com/f2/onboard-air-3027/

http://www.cherokeeforum.com/f58/lets-kick-around-ideas-trail-air-compressors-21849/

http://www.jeepforum.com/forum/f140/sanden-onboard-air-system-write-up-742180/

 

http://www.s10forum.com/forum/f125/official-sanden-thread-215865/

This last one is the most comprehensive and covers several ways to do this on a Sanden. These guys run their compressors at their normal operating pressure of roughly 300psi and do it all day.

 

I've though about tackling the EA82 hitachi compressor like a sanden, but the valving is different and it draws fresh air through the compressors crankcase. I recently acquired a York compressor and I think I'm just going to use that instead, because I know they work awesome.

 

AMC/Jeep 4.0l's are notorious for blow by and I've seen guys run their OBA setups with their intake on the PCV system and it gets really nasty in the compressor, which can lead to premature failure, and the oil seperator.

 

-Josh

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Using a York is the easiest and most reliable way to do this. Also, the old giant Chrysler units will outperform a York, but they are getting hard to find and are more difficult to convert.

 

I've done a few York conversions on vehicles over the years.

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Why not run a 12V compressor and have a 3-5 gallon tank?

 

I'm planning on doing that to my trail rig, add in a 120psi pressure switch to shut off the compressor when the tank is full and i'm all set, If I add a relay to the ignition circuit I don't even have to worry about it going off all night if I get a sudden leak in the system.

 

All harbor freight parts, added an extra heat sink to the compressor per Subieclimbs and the price was about 500 less than the comparable ARB fancy pants parts.

Edited by NoahDL88

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Thought about it, but that would take up more space, and probably cost more, whereas if your car already has AC that's likely already not working, might as well use it, right? Plus, A/C compressors can put out pretty good pressure and volume. I've read that most folks can fill a big tire in about 60 seconds, and can even run air tools. And since an AC compressor is designed to run refrigerant at about 300psi, as long as you keep it lubricated, it will probably last a while. Not to mention a helluva lot quieter.

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Why not run a 12V compressor and have a 3-5 gallon tank?

 

I'm planning on doing that to my trail rig, add in a 120psi pressure switch to shut off the compressor when the tank is full and i'm all set, If I add a relay to the ignition circuit I don't even have to worry about it going off all night if I get a sudden leak in the system.

 

All harbor freight parts, added an extra heat sink to the compressor per Subieclimbs and the price was about 500 less than the comparable ARB fancy pants parts.

 

I've seen this done before too, and the 12V systems take FOREVER to fill a tank a 3-5gal tank, they don't move enough CFM's. A compressor like a Sanden or a york are like a 110V compressor and can fill a 5 gal much much faster(like 30-45sec.), depending on what compressor your using. Everybody I met that has tried using an electric compressor for OBA has either switched to a real compressor or wish they did. An A/C compressor with a 3 gal tank can also keep up with an impact gun making trail repairs much easier. A 12V compressor can't do that.

 

-Josh

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I'm surprised no one has mentionned ARB off-road products. They have 4 compressors that deliver outstanding performance and reliability.

 

A permanently mounted compressor has the advantage of not taking up precious cargo area. But if under-hood space is at a premium, there is a kit that comes in a carry case with all the accessories you need. I have an off-road modified 2003 Nissan Xterra with ARB lockers and on-board air. A must for serious offroading.

 

For the Subaru, on extended trips to remote fishing and camping areas: two cheap compressors do the job. Use them both to accelerate inflating the four tires. If one fails, I have the 2nd one !

 

(I do not sell ARB products - I'm just a user and a fan !)

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An A/C pump compressor can keep up with these too!

 

 

:eek:

 

Lol yup! I've been eyeing that PCV horn setup lately. Would work well with a compressor conversion.

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I've got a 1986 ea82 using the stock A\C compressor as onboard air for a long time without trouble, use a few drop's of duralube or some kind of slick oil aditive for lubercation every other use. The compressor work's great for air horn's, tire inflation, tools, & blowing out my filthy ride. I have seezed the pump on hot day's , but it will unseeze & work again usualy once or twice. To oil the compressor turn it on & pour a little down the suction side, I haven't run it with a filter for year's, but that depend's on how dusty it is when using the air, use a pressure switch, blow off valve, air tank,& dash mounted switch for the pump

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I grabbed a couple of Cadillac air ride compressors a while back.They seem to put out alot of air.For all I know I may have already posted that :) LOL:horse:

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I am going to do this on my Legacy- with the stock A/C compressor...

 

I will take lots of photos, and do a full write up of how it's done, when it's done.....

 

 

My opinions on why you should use the A/C compressor over the electric ones-

 

1) you probably already have an A/C compressor on your car, and if the car is as old and beat as most of the ones I see on the forum, it probably does not blow cold air anyway.

 

2) it already has all the "connections" it needs to run off your engine- provided your belt is still there, and you have enough wire to connect the 12v signal to engage the clutch...

 

3) it can probably be used almost continuously (as long as it's lubed) and it wont have overheating troubles....

 

4) volume of air... (as stated earlier in the thread) to inflate either a flat, or 4 aired down tires is much quicker and easier if you have your car just idling and an onboard air tank already full (from when you were driving and compressing)

 

5) (most importantly) its cool :cool:

Did you ever do this? How well did it work? I'd like to do it on my 99 Outback, AC has been ripped out for a while but I still have the compressor.

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i love my ac and my inverters and yes i can run a skill saw off of a inverter or just about anything that dosent require clean power ive run a small cabin off the inverter with a tv computer lights and radio for hours never tryed a compressor though they do make high cfm 12v pumps ive had a few good ones but they do always fry i have in a pinch used my exaust to inflate the tire i got to 20psi in seconds but thats all i could get out of it but hay its enuff to get back on the trail and to a gas station it was just the hose from the fried compresor wraped with cloth pushed up to the exaust pipe while someone else was reving the engine its not easy but it dose work ive also herd of pulling a spark plug and screwing in a air hose for air on the trail i dont know if you could or would want to run air.tools like that though

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Has anybody here ever tried the spark plug oba trick?

 

For those that don't know, you take an old spark plug and bust all the porcelain out of it along with the electrode. Now you have a threaded tube that fits in the head and after that all you do is weld which ever quick disconnect you wan to use on the end of it. You use it by simply taking out a plug, putting this modified plug in and hooking your air hose to it and what ever attachments your using. 

 

One issue with this is that the air thats going in also has fuel mixed with it, but I've never heard of anyone having problems with it in regards to its affect on tires. The likely hood of something going boom is really low, unless all the air in there came from the motor. The solution for this is a injector kill switch, so that when your pumping air, no fuel is coming out of that bore. The air coming out also pulses, so running air tools is out, but it fills tires really fast. 

 

You used to be able to buy these things off the shelf, but I haven't seen them in a long time.

 

Josh

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With fuel injection it would be even easier,just disconnect the injector for whatever hole...Although using the AC compressor seems much easier because it normally isn't too hot to touch.

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