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ORO's On Board Air System

Off Road Only On Board Air

Part #:

I ran AiROCK on a past Jeep and patiently waited for Steve at Off Road Only to release his AiROCK kit for the JK's. Off Road Only did come up with their own On Board Air System for the JK's, so one was sent to me to prototype and see how the installation would go. This kit comes complete with the Onboard air system and is prepared for AiROCK, so you don't need anything else for it. This is one of the very first kits put out, so there may be some changes from this kit into the future.

Additional Parts:
10w-30 Motor oil (non-synthetic)
Teflon tape

Tools Needed:
Tubing cutter (provided by ORO)
Floor Jack
Block of wood
9/16” Socket
1/2" Socket
3/8” Socket
7/32” Allen wrench
3/16” Allen wrench
15mm socket
16mm socket
17mm socket
19mm socket
15mm Combo wrench
16mm Combo wrench
17mm Combo wrench
19mm Combo wrench
9/16” Combo wrench
7/16” Combo wrench
3/8” Ratchet
4” Extension


Some helpful Compressor Info
CCI Service Manual


The compressors from Off Road Only come already assembled with the clutch installed. I left this part in here, just in case you want to see what assembling the compressor clutch is like. I had a bad pulley on my clutch that wobbled and I needed to change it out.

Assemble the compressor:

1. Install the magnetic clutch onto the compressor housing.  I decided to install the clutch with the wire on the top so that it was out of the way of the belts.  Thread the four bolts into the housing then tighten with a 3/8" Socket.  Tighten the four clutch mounting bolts to 13-19 ft. lbs. (17.6-25.8 N-m).  NOTE: Only use bolts that have a loctite patch on the threads.

2. Install the pulley onto the shaft.  Align the keyway in the pulley with the key on the shaft of the compressor. 

3. Then insert the washer onto the bolt and thread the bolt into the shaft.  You will need a 1/2" socket to tighten the bolt.  Tighten the clutch center bolt to 20-25 ft. lbs. (27.1-33.9 Nm).

Changing the oil:
Off Road Only changes out the oil for you and should come with a tag. Mine spent some time upside down, so a lot of oil was in the box. I felt it was prudent to redo the oil in it.

We will need to drain the refrigerant oil out of the compressor.  The York compressors come with oil that is designed for use in a refrigerant system.  Since we will be using them as an air compressor we will need to change the oil out.  Normally these compressor only have about 12-16oz of oil in them when they come from the factory. 

1. Remove the oil fill plugs from both sides of the compressor. 

2. Tip the compressor over onto one side and allow the oil to drain out into a measuring cup, this will give you a good indication of what was in the compressor to begin with. 

3. Once all the oil has drained out, wipe the oil hole clean, and reinstall the oil fill plug on the left side of the compressor.
Note: When inserting the oil fill plug, the sealing “O” ring is slipped over the oil fill plug threads in such a manner that the “O” ring is not twisted.  Insert the oil plug in the oil fill opening and tighten the plug snug.  If the plug leaks, do not attempt to stop the leak by over tightening the oil
fill plug.  A leak may be caused by dirt under the “O” ring or on the seat, a fractured “O” ring, or a damaged seat on the oil fill plug or oil fill opening.

4. Lay the compressor on its side with the open oil fill hole up.  Using a small funnel, pour 12oz’s of 10w-30 (non-synthetic) oil into the compressor.  Take your time, or you will make a mess. You can also do this with a turkey injector if the small funnel doesn't work.

5. Install the oil return fitting (Brass JIC3 - 1/8" female with o-ring) in the oil fill hole.  Do not over tighten; you will damage the o-ring seal.  Tighten down with a 9/16” combo wrench. This will go on the right side of the compressor as you look at the clutch assembly
6. Install the 1/8" npt - 1/4" push in elbow fitting into the oil return fitting.  This will require you to hold the oil return fitting with a 9/16” combo wrench and tighten the fitting with a 7/16” combo wrench.


Installation Instructions
Top Bracket Air Compressor Bracket
Air Tank and Lines Harness Modifications and Additions


N-m Ft. Lbs. In. Lbs.

Cylinder block-to-insulator mount bolts



Timing chain cover bolt M8 bolts



Timing chain cover bolt M10 bolts



A/C Compressor Bolts




YORK Compressor


Clutch mounting bolts




Clutch center bolt




This page last updated: 16-Apr-2008

Content and Design © 2002-present WanderingTrail,  Ron Seegert
Common Sense and Safety should always be observed when working on your vehicle or doing modifications. Jackstands, wheel blocks, disconnecting the battery are a few of the basic safety precautions that should be used and may not be mentioned in the write ups on this site. You are responsible for your own installation, these write ups are a helpful guideline and should not be taken as an official installation instruction. My write up may be different from the kits currently out there, so alwasy double check the manufacturers installation instructions when installing anything. I try to keep the site up to date with changes that have occured as I discover them, but may not have the latest unless someone lets me know. If you feel that an install is above your capabilities after reading my write ups, I recommend getting together with a club and getting some help. Only a few times have I needed to employe some actual help from a shop to get something done. Usually welding or A/C work.
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