Onboard air using stock compressor

Well i am pretty poor at this time and I would really like a way to fill my tires up after I air them down on my rig. I did some research and found a great writeup on doing this with a stock jeep compressor. http://jeep.off-road.com/jeep/article/articleDetail.jsp?id=260374 SO will my compressor work ok with this setup or am I just waisting my time? Also I need some suggestions on places to get all the fittings needed for this.

I say this is very doable and if you reread the article he used a Ford Mustang compressor, my only area of concern would how he hookup the lines to the compressor itself. As far as finding the fittings i would think a decent hardware store would have them.

I have been using mine for a couple months now, I get some pictures up later

Here's a diagram from that website:

This link is # 50 in my list of useful threads: http://www.explorerforum.com/forums/showpost.php?p=1648737&postcount=5

yea the diagram from the article is helpful. I think the hardest part is plumbing the whole system with all the right fitings. I already have the compressor mounted in there so the hardest part is already done. Now its just a matter of taking out the stock AC stuff and putting in the onboard air stuff. I plan on mounting a 5 gallon tank where the spare tire goes. It may be a little big(they suggest 1-3gallon) but the bigger the tank, the less the compressor has to kick on.

You could get a tank to mount underneath the vehicle to save space. Harbor Freight sells a 7 gallon tank in aluminum which might be better for exterior mounting. http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=94801

Most of my setup was made with parts I had on hand.
The intake side of the pump needs to be as freeflowing as possible because it does not have alot of suction.
I have mine set up like this
airfilter-oiler-pump
pump-one way valve-seperater/filter-pressure switch,pop off valve, air tank

In the picture showing the air tank the first hose on the left is from the pump/one way valve and the second hose is going to a 'T" fitting by the frame rail that splits to the front and rear air fittings mounted on the front bumber and under the rear hatch

That Harbor Freight tank is nice but it's a little pricey probably have to find something else little cheaper. but it got me thinking tho, already priced out most the parts so far it's under a 100 dollar bill but i haven't priced out the hose and a tank yet and all the fittings needed.

but this defintly beats the snot out of the off-the-shelf oba's i have seen for 400.00 and up

yea I think its a great idea. Today I'm going to start pulling out the stock ac crap and make a parts list for the hardware store. There might be a good writeup in my future

There are a few ways to get the lines onto the ac compresor. I fyou have a custom hose fitting shop around (like I do) then just take it to them and say, I want those lines to have a female 1/4 NPT quick coupler.

Or, if you are handy with a mill, ive seen people make a block the bolts on just like the stock one does, and is tapped on the other side for fittings.

Or, if you are brave you can try and tap the holes in the comp itself. I would try and stick a magnet inside just to make sure no shavings get into it.


The rest is just a piece o cake, any hardware store should have everything you need.

I would try and keep the tank small, a big tank takes more room and is easier to come down on a rock.

The lines are already connected to the compressor, just cut them where you need to and use a barbed fitting with hose clamps, leave the high pressure hose as long as possible because of heat

Did you consider using stainless steel supply lines like the type they use for plumbing fixtures (faucets, and toilets)? They could withstand more heat than bare rubber hose since they have a stainless steel covering.

I was at a Harbor Freight retail store last weekend, and they had one of those aluminum tanks left which was on sale for $50. The online prices don't always match the price in retail stores.

I see a combination of brass, galvanized, and black fittings. It's not a good idea to mix dissimilar metals which could rust. Use all brass or bronze fittings.

jrgaylor- what did you do for the switch? Did you just leave the stock AC nob and just turn the compressor on with that or did you wire in a new switch in the cab to activate the compressor?

I use the knob in the dash as my master switch and I have a pressure switch at the air tank (on@80psi off@120psi)
I spliced in my pressure switch inline with the factory wiring to the pump.
Also over by your airbox there is a pressure switch for the factory A/C that need to be spliced together to by pass the switch.

I got a couple of questions for those of you who know. I picked up a Furnas pressure switch with an unloader valve. It was 6 places to hook up wire. 2 say motor, 2 say line and 2 say ground. I am just going to hook in a whole new switch for the system so How will I do this? And the other question is, can I just cap off the unloader valve and not use it or is there a use for this valve?

o and is the intake side of the compressor the right or the left when looking at the front of the grill? I figured th intake was on the right going up to the grill and the output was on the left going to the firewall.

The pressure switch is a double pole, single throw switch. The 2 which say line are the parts where the power would connect to. The part which says motor go to the electric compressor, or in this case the electric clutch. You could cap off the unloader unless you want to install a check valve with the port for the unloader. The ground is just the vehicle ground which could either be connected or left alone.

the hose going to the grill is the output (high pressure) side and the line coming from the firewall is the intake (low pressure side)

the unloader valve bleeds off pressure between the pump and the check valve so that the pump will not see a load on it when it first starts. I did not use this feature

Thanks a lot. I'm g;ad I asked because I had it backwards