TOTM: On Board Air (OBA)

[ashmanjeepXJ]

Welcome to the next contribution to the
The Official Pirate4x4.com Jeep Talk Bible

Topic of the Month On Board Air (OBA)

The On Board Air (OBA) tech topic will focus on belt driven air pumps/air compressor.

Typical OBA setups re-purpose an AC Compressor with an outlet going to a small storage tank using an electric pressure regulator to open the clutch on the compressor when max PSI is reached. The challenge with the OEM AC compressors for this application is lubrication, The closed loop Freon they were designed for is also charged with lubricant.

One solution is to have an intake filter to keep dirt out of your pump, oil injector to keep the pump lubricated, Oil filter to keep your air dry, check valve on the output, electric pressure switch to the clutch, reservoir tank. Oil in your air is ok for air tools but not good for airing up tires.
Pirate user 1996cc's setup in a cherokee



Another solution is to modify the AC compressor to have grease fittings that allow external lubrication, with goals to keep the air dry from oil.
XJOREGONDIRT's project /forum/jeep-cherokee/843027-xj-board-air-system-using-sanden-compressor.html

The most common OBA compressor chosen is the YORK brand AC Compressors. These are well known for their oiling design that allows them to be run as an air compressor with no added oil injector. You may need to block off the oiling hole, I think this is mounting orientation dependent. These compressors are large in size compared to the stock Jeep compressor and require custom mount modifications. They are found under the hoods of 83-90 Volvo 740 GLE or 760 GLE with the 2.3L turbo 4 cylinder motor, also 80s Volvo F210 models, Most AMC Wagoneers.

This thread does not include electric battery powered OBA setups and does not include CO2 portable OBA setups. Those off the shelf systems are relatively easy to install and do not need to be covered here.

Similar pirate4x4 tech threads
JEEP section OBA TOTW
ARB electric OBA compressor

[xj9140]

I am wanting a belt driven compressor wile retaining my Air Conditioner. Who has done that? Kibey offers a bracket on there web sight for a '91-'98 TJ 4.0. I wonder if it would work in our Cherokee's engine bay?

[nattyboh]

no pics but i used my stock accompessor it intakes from my aircleaner box across the firewall through a checkvalve then an inline tool oiler then the compressor.then to a water/oil seperater airline then routed through cab to a tank off a semi with a pressure switch with a dumpoff to relieve pressure off the pump for the next cycle.
i just have to keep an eye on tool oil level.it pumps out some air.it will fill a 5gallon air tankfrom 0 to 115psi in about a minute. i left it hooked up to the factory ac switch.

[climbit]

subscribing. I am thinking of re-locating the battery to where the current airbox is and fabbing a bracket to sit a compressor (maybe a JY A/C comp) next to the current one.


of course that involves a cowl intake as well.

I know somebody has done this, or at least has time to do it.

[GreatWhiteXJ]

Subscribed. My first attempt 6 years back was a MASSIVE failure.

[miteclgst]

Here is a link to my OBA Build... only used it once and it worked well.. built around the stock AC compressor: Click Here

[flexy92xj]

Here is how I mounted my York... ditched factory AC, cut up the factory AC mounting bracking and fabbed up an adapter to hold the york.

[XJ ABUSER]

A couple years ago I bought this setup from a guy here locally in Colorado. It is a York compressor. He goes by frank z on all the sites (pirate4x4-naxja-colorado4x4) so some of you might know him. It's a simple bracket and I can try to take more pics if needed but this should about cover it. I think i remember using a Chevy 1500 belt (no idea the year) but I can't really remember.
Let me just say I know my engine compartment looks like a rats nest and it will probably catch fire and I'll burn in hell.









I had to bend the ac hard lines farther up by the radiator. I know my belt looks worn weird cause I had another issue and I'm f-n lazy. I carry my original belt as a back up in case anything goes kaboom. Ooh yeah and i think i remember having to clearance where the battery use to sit with a BFH. It's worked great for years. It's On a 97 xj

[FrankZ]

[trblmkr4]

Subscribed

Sent from my DROID BIONIC using Tapatalk 2

[GeneticDisposition]

Well that looks far to simple.

[lodikrawlingkiller]

ok so i have to throw this in there. ZJ compressors are totally different. they use a type of double barrel piston and also they have a funky valving system. ill get pics when im at home on my own computer.

[EddieXJ]

I have a basic write up on this subject at my club's website:

http://overkilloffroadclub.org/the-b...t/onboard-air/

Used a mist-type oiler to provide more oil to the compressor than the tiny little air tool oilers. I run ATF through mine

[TheHNIC]

Has anybody else hit a brick wall sourcing for a 6 rib pulley for a york compressor? Kilby seems to have to most easily found unit but $270 makes my cheap un happy. Ideas?

[lodikrawlingkiller]

Zj pump internals.

[lodikrawlingkiller]

I went the grease route with my zj pump. Cleaned the he'll outa the internals filled with Lucas high temp high speed super tacky red grease. The drilled and tapped the case for a zero fitting. Haunt had a chance to run it yet though.

[Repmo]

I use York 210 compressor, from freightleiner truck to have 6V belt, installed on stock AC bracket



I have machines new head for compressor for maximum flow and keep more oil inside, I have plugged return hole in compressor, I use the same air filter as the engine


My small air tank was just a maniful to go on each tires, I use the magnetic clutch to increase pressure in tires and solonoid valve to defleate tires... I control this with small controler in the dash


I can inflate or defleate the 4 tires in sames times within 1 minute on the road...

[TheHNIC]

Mother of god! You wanna be a real cool guy and sell them on here ?!? Or better yet send me the CAD drawing for the york head!?

[EndlessMtnFab]

I'm interested in information on that head unit as well. Spit it out.

[GeneticDisposition]

I don't think I want to know how much that setup cost! Its fucking sweet though.

[DeftwillP]

As if portals weren't cool enough....

[TheHNIC]

I guess now that my OBA is nearing completion, Ill post up what Ive done.
Id like to thank Guidolyons for helping me figure out which pulley I needed to get. I could have gone and spent $400 with Kilby but thats not my style! I found a 6-rib pulley from a Freightliner parts list:
A/C Clutch 5 7/8"Dia 6 Groove 1wire, 5030, Airsource - Ryder Fleet Products

It fits perfect but i think the taper on the york snout is a little different; i dont think its going to be a problem but time will tell. I measured and made a 3/8" aluminium plate. The belt ended up being the same as my '96 Tahoe (96 1/4" IIRC), so belts are readily available.

Finished Product:





Next project is to do a cylinderhead like Repmo:

[Bronco II]

What's going on with that new machined head? I want one!

[favaguitars]

There are a Few i have seen with a york mounted driver side. I wonder if any of them will post up. No battery relocating.

[TheHNIC]

Originally Posted by Bronco II

What's going on with that new machined head? I want one!

Truly want one? I have a 3D model made right now. Post pics later.

Found this website today for those who need an 8 rib. Trying to do a York on my tow rig!
A/C Components by ValAir Inc - High Performance Clutches for Dodge Cummins and Ford Powerstroke Trucks, G56 Conversion Kits, Ceramic, Feramic and Kevlar Clutches