Background:

Compressors are a big part of a wheeler's life. You notice your fender is getting mangled by your tire so you whip out your cut-off wheel. You want to swap out your "street" mud-terrains for your Swampers so out comes the impact wrench. But many of us are forced to go to a gas station to fill up our tires after a day of wheeling or spend an eternity with the cheap electric compressors since our powerful compressors are stuck at home.

Here's where onboard air and the York compressor comes in. It's a large, piston-type compressor used for AC in the 70's and 80's in AMC's, Ford's and Volvo's (and probably others).

The first benefit of the York is that it has it's own oil resevoir. If you use one of the more current rotary compressors (such as Sanden) for onboard air, you need to use an oiler since the refrigerant (such as Freon) lubricates the compressor when used as AC. Without an oiler or the refrigerant, you will burn up one of these rotary compressors.

The second benefit is that these compressors pump A LOT of air. There are a few different displacements of these compressors and the most desirable is the 10.3 cubic inch version which is what Andrew got out of a 1980 Ford Thunderbird.

It would have cost him $35 but with Gus' negotiating, he got it for $23. The 10.3 ci York pumps something like 4 cfm @ 90 psi just off idle and I've seen data showing 10 cfm's at 3000 rpm. That's a lot of air!

Determining the size of the York can be determined easily by going to Kilby Enterprise's Onboardair.com site and going to the York ID link.

Mounting Options:

Once you have the York, you need to determine how you're going to mount it. In our case, the York was being installed into a 97 TJ with the 4-banger, no factory AC and a 1" body lift. There are really two options for mounting the York. The first option is to mount the York to the stock AC bracket and run a new longer serpantine belt as if we had stock AC. The second option is to hang the York to the right of the AC bracket and run it from it's own belt. (The second option is the only real option if you have factory AC and want to keep it.) Kilby Enterprises provides mounting brackets for both of these options.

Another thing to realize is that not all Yorks are the same even if they are the same displacement. If nothing else, they have three different types of heads (suction/discharge fittings) and three different types of stock pulleys. Kilby's prefers the flange style heads and provides low profile fittings in many of his kits. We, unfortunately, had the Tube O heads, but Kilby has some fittings for those too. (He also supposedly carries the Roto-Lock fitting as well.) We also had the single V-groove pulley on our York. Kilby's kits require either the double V-groove pulley if you want to use the separate belt for the York or the 6 groove pulley for the serpantine belt. (Kilby sells new pulleys of either type along with new Yorks as well.)

Parts:

So, either way, we needed a new pulley, so we went with the serpantine solution since this option is cleaner and eliminates the possibility of having to do some fender "clearancing". Andrew ordered the KE-1550 kit from Kilby Enterprises which provides a mounting plate and hardware to mount the York either horizontally or vertically on top of the stock AC bracket.

He also bought some low profile Tube O fittings (since the stock Ford fittings were much too tall) and a new serpantine pulley/clutch.

An intake filter was also purchased from Kilby since he sells a very nice one that flows enough air to keep up with the York.

Installation:

We first removed the old clutch/pulley and began to assemble the clutch on the York. The bolts provided with the kit already come with thread locker on them. Nice!

These need to be properly torqued to the spec in the directions.

Next, put the new pulley on and use the new bolt and washer.

This also needs to be properly torqued to spec. We did not have the proper tool to hold the pulley stationary, so we torqued it down as best we could and then torqued it to spec when the York was mounted to the vehicle and we could lock the clutch to help everything from moving.

The new clutch comes with a nice, new connector as well!

Next, we mounted the Kilby bracket. Here's the stock AC bracket. Notice the Turbo City intake. This is required in order to make room for the York...especially critical if you use the other kit that Kilby provides as the stock filter box is right in the way.

At this point, I torque down the bolts to spec. Notice that you have to insert two of the York mounting bolts before torquing down the bracket. This is all detailed in Kilby's instructions.

You can then sit the compressor on the bracket. In our case, the 4 banger and the 1" body lift allowed us to mount the compressor vertically. On a 6 cylinder, this would not have been possible unless there was a taller body lift. However, the compressor can be mounted horizontally and Kilby's kit comes with the correct length bolts for either option.

Torquing the bolts holding the York on the bracket can be tricky, especially the one in the rear closest to the engine, but it's doable.

I then installed the fittings.

We then added the air filter to the suction port of the York. The Tube O fittings that Kilby sells are NOT 1/2" NPT (which the filter requires), but the threads are close enough for illustrative purposes. We need to get some adapters.

Next, you have to get a longer serpantine belt. The instructions tell you to get the belt from your model of Jeep but with AC. However, I've heard that this belt is still too short and is in fact around 4" too short. We used a string to measure the approximate length of the needed belt and we went to Napa. The belt for an AC equipped 4 banger TJ was in fact around 4 inches too short. The stock AC serpantine belt was 91 7/8" and we got a belt that was 96 1/8". (Napa Part # 060956). This belt turned out to be a perfect length! Here it is mounted:

We used a piece of wire to lock the clutch and yes, boy does that sucker pump air (and some oil)!

Tank/Pressure Switch

Next up, we mounted a Kilby 2.5 gallon tank on the passenger side fender. We used 2 of the 4 mounting holes on the tank.

On of the mounting holes is right under the fuse box shown on the left so it needs to be lifted out of the way to reach the bolt.

Once the tank was mounted, we installed the pressure switch on the passenger side fender as well.

Finally, we hooked everything up!

Here's a shot of the gauge Andrew added to the back of the tank.

On the right side, we hooked up the pressure switch and a quick disconnect fitting.

The front hole we plugged up and we put the pop/safety valve in the top hole.

The left side has the input coming from the compressor (via the filter) and it too has a quick disconnect fitting.

The complete setup! Some will notice there is no regulator, but this setup is to fill tires...two hoses at a time.

Wanna see pics of a smoked York Compressor?? Dead York Pics...