onboard air - what do you use?

[kastein]

I am new to this idea, but considering the previous owner removed all the air conditioning lines, and i removed the ac/heat controls from the dash to mount a CB the other day...
i'd like to run OBA off my ac compressor.

so far what i've gathered from this thread is the stock AC compressor won't do it? i need to go pull a better one from a junk yard and get a new mounting bracket?

The stock compressor would do it fine except for one issue - it isn't self lubing, it uses lubricant mixed in with the refrigerant in the lines. The York compressor is favored because it has a separate lube circuit/reservoir. Some people have run stock compressors and just pumped a small amount of oil into the intake to keep them happy, but that results in oil in the compressed air lines and I don't like that personally.

EDIT: zr2toxj, VERY good point with the shutoffs. I didn't even think of that - luckily () I don't have lockers to worry about yet!

 

[arctycfox]

I dont know about 2. Maybe if you made a bracket and stacked them on top. I have my fenders cut and folded back there so mines a little different.

Yeah I was figuring on stacking them with a custom bracket, just worried there wouldn't be enough room. Did you have to address overheating? I was thinking of putting 2 4" or 6" 12v fans in a push pull config to circulate air through.

 

[AshyLarry]

Yeah I was figuring on stacking them with a custom bracket, just worried there wouldn't be enough room. Did you have to address overheating? I was thinking of putting 2 4" or 6" 12v fans in a push pull config to circulate air through.

I dont have it finished yet, I just moved it there this week. The panel needs cut for it to fit anyways. I have a piece of Plexiglas that I am going to drill some vent holes in and put over the trim I cut.

Since the thing isn't on very much I dont think there will be an over heating problem. At least I hope it doesnt lol

 

[yossarian19]

I would think a 6" fan in a pusher config, behind the plexi & trim, would do it just fine for airflow. Just put a few holes out of sight in the 1/4 panel, maybe block off other air channels just to make sure the air flows properly... maybe more involved than I'd want to get but should do the job.

 

[jmop]

I'm running a York for OBA, built the bracket myself since I'm running a second alternator for OBW in the factory AC compressor location. I picked up an overdrive v-belt combo pulley from Kilby for the OBW so I can use the York's v-belt pulley.

Works great, I can air up tires quickly at idle, no tanks to lug around or refill.

Most of they guys I wheel with either have OBA or CO2 tanks. Both have their good and bad points.

 

[AshyLarry]

It wont get hot enough to need a fan, the vent holes should be just fine. It only runs for a few minutes at a time, then has plenty of time to cool down.

 

[MaxxXJ]

i went ahead and bought a nitrogen regulator and hose/ air chuck for the tires, i rented a 76 cu ft bottle for the weekend to see how i like it, hopefully it does the job well, if so i'll be buying me a bottle to keep around all the time. maybe a bigger bottle if i like the size better i think the next size up is 106 cu ft so it shouldnt be all that much bigger... i'll post up sometime after sunday about how i like the nitro bottle...

 

[Paul Airhart]

Here's mine, a little work but out of the way.

 

[kastein]

Paul - that looks almost exactly like what I intend mine to be as soon as I build myself a rear bumper with a spare mount on it. Is that a 120mm muffin fan blowing on the compressor?

 

[Paul Airhart]

Paul - that looks almost exactly like what I intend mine to be as soon as I build myself a rear bumper with a spare mount on it. Is that a 120mm muffin fan blowing on the compressor?

Yes it is, it helps to keep air moving over the head/cylinder. Gets hot out here.

 

[fyrfytr1717]

I didn't want anything in the cargo area so I opted for mounting my compressor in the engine compartment and my air tank under the cargo area floor, above the rear axle.

I've got ABS so I couldn't use the typical engine compartment mounting spot next to the brake master cylinder. I already had a K&N FIPK installed and found that if I mounted a shorter, fatter Amsoil cone filter instead of the original K&N, I could get nearly the same air flow and open up just enough room for a Viair 480C.

Before:

After:

 

[Paul Airhart]

After:

Are you not concerned about moisture?

 

[MaxxXJ]

ok so i finished my weekend trip and heres the deal... i used my tank on 2 other jeeps with 35's and my jeep sitting on 235's currently, we all were running approx 12-15 psi and aired up to approx 30 psi, well my starting tank pressure was 2200 psi, after i finished airing up 12 tires it was down to about a 1000 psi, btw it took all of 5 minutes to do all 4 tires. well i took it home and filled up my dads car tires 245/70/15's( been sitting in the garage on his project chevelle for 6 months and lost pressure so again, approx 15psi to 30psi, after playing with the air tools i finally got the pressure below 500 to say the least im very impressed with the bottle, its a med sized bottle so it takes up some space but im willing to trade space for function. my point to my outcome is ill be buying a bottle soon instead of renting them this was well worth it to me

 

[fyrfytr1717]

Are you not concerned about moisture?

Not really. Should I be? What type of moisture are you referring to? Water crossings, rain, steam from the radiator cap? Lots of folks mount their compressors in the engine compartment. The compressor intake is actually higher than the engine intake so if it gets dunked during a water crossing, I've got bigger issues. Remote mounting the inlet filter for the compressor is an option as well, I just didn't feel it was necessary. Honestly, I was more concerned with heat.

 

[AshyLarry]

How much was it for a tank maxxXJ?

Bungs welded onto my sliders now. They had to be touched up once each, so they dont look perfect, but hold air.

 

[AshyLarry]

 

[arctycfox]

nicely done. Plexy?

 

[XJ Beater]

i used the stock ac compressor, ac clutch on a toggle switch for now until i can get a pressure switch, got an old r-134 tank from work, welded a airhose fitting to it, hose from compressor into tank, output from tank has a valve that works perfect as a regulator, runs the airhorn and fills tires from 0psi to 30 in mabue a minute, also runs an impact pretty well, next is pressure switch for automatic on/off, and some sort of oiler system, for now it gets some 20-50 oil dumped in the intake once a week and i run an oil seperator in the airline to remove the oil before the tank. works great! cost-mabye 20 bucks so far

 

[MaxxXJ]

How much was it for a tank maxxXJ?

to RENT the tank it was something like 14 bucks for a 76 cu ft tank, i think thats also the refill price, rental was something like .44 cents a day, used it for the weekend it came out to less than 20 bucks, to BUY a tank its approx 160 dollars, but if i can use it on 5 sets of tires before i run out of air, i could go on at least 5 trips with 1 tank... so im thinking 30 bucks a year after i buy a tank? not bad imo especially while those 2-5 gallon air tanks fill up like 1 33" tire if that and your still sitting there for 15 minutes airing up your tires while im either gone already or sitting back in the shade drinking a cold soda =)

 

[Paul Airhart]

When I air up with mine, there is no waiting. The compressor comes on and continues to fill the tank, hence the tire. And I have 33's.