On board Air using AC compressor questions

I installed on board air on my CJ7 a few years ago but never really used it. I never actually finished it completely. I was using a Sanden type compressor because I had one that fit the engine. It was set up completely manual. I had a safety valve but no pressure switch attached.

Several people informed me I did it completely wrong and that my Sanden compressor would never last. I was told I needed to use a York compressor because they had an oil sump and could contain their own oil.

Well I'm ready to install on board air on my M715 now. I have a Harrison compressor already on my 6.2 that has a serpentine belt setup. I plan to use the Harrison pump as the air source. I've long thought any AC compressor would live fine pumping air as long as they were well oiled.

That brought me here.

What I'm wondering is how will I vent my Harrison crank case? The video doesn't have very good pictures of the components in use and is also using the Sanden type compressor.

Anyone here set up with on board air similar to the way the video shows his set up?

I already have a tank mounted to the bed tool box that measures out to about two and a half gallons of air storage. I also have a check valve, a safety blow off valve and a pressure switch as well as the dash switches to control everything.

I just need to figure out the oiling system really. Anyone have any experience with this that can steer me in the right direction? I don't think I have enough smarts to invent the wheel so to speak.

AC systems circulate the freon which has oil mixed in it. That's how the compressors live.

The York however has its own oil reservoir separate from the freon and as far as I know the only one that does.

The issue with using a non York is that you have to keep supplying oil to the air intake, which is then also passed on in the air you are pumping. It can be done but is more work then it's worth to have a oil supply and removal system.

Ok I watched the vid now. I see what he has going there and all makes sense. But you don't need any of that if u just use a York. It has a built in crank case with oil that never mixes. Ok sure some oil may get by the rings, but no more then your home compressor. If it does then it needs to be rebuilt.

I guess I should have watched the vid first, I know nothing I wore answers your question. I would still vote just get a yoke. Lots of them out there and lots of info on using them.

I have a Tecumseh pump which is the cast iron version of the big York. I have two problems trying to use that. First it is a v belt and second there isn't enough room under the hood to mount it.

I've actually even looked at trying to power it from my PTO but there really just isn't enough room anywhere I can find to power the Tecumseh

I'm thinking all the effort to oil the compressor properly will be worth it if I end up with a long lasting reliable compressor. I just need to figure out how to properly oil the compressor and keep the oil out of my air line. It sounds like venting the compressor is the key but I'm not versed enough in compressors to know where to put the vent.

if you check out jeepforum.com and naxja.org, there are plenty of people running sanden type compressors for on board air. The york is still the preferred compressor but doesn't always fit. To run the sanden, you need to add an in-line air tool oiler at the intake, and an inline oil seperator at the outlet... Both are pretty easy to find from what I understand

York compressors, do in fact have their own sump. So do some Harrison compressors. The A6 has a sump and even has a drain plug for it and an internal oil pump. It makes an excellent choice for an air compressor, but it is big, and weighs a ton. It also only comes in a v-belt configuration if I remember correctly. If you aren't running it for long periods of time, most compressors will work fine and with an inline oiler, you'll most likely be fine.

Be sure to just use a fairly long length of hard tubing from the outlet, before you transition to rubber hose or it will melt off in short order. The outlet of the compressor will get very hot in normal use.

If I ever get to my onboard air, I am planning to use a small, cast iron, piston-type air compressor I robbed from an older contractor compressor. My plan is to mount it on the engine, then drive it all the time from a belt, using a Deuce unloader valve to regulate the air pressure in the tanks. It has its own oil sump, is pretty compact and should work fairly well. That is if I ever get to it.....:rolleyes:

I did OBA on my M715 back in 2005. I installed M35 air tanks under the bed, ran hose to both bumpers with quick connects, made a York compressor fit and did the oil passage block on the York.

I loaded up air hose and air tools in the tool box and when I had a flat on a trailer, I got them out, fired up the compressor and used the impact to change the tire. I thought it was the best thing ever.

At the 2006 National FE in Tennessee, I aired down my XZL tires to 12 psi or so. I wanted them back up around 50 for the 800 mile drive home. I had trailer issues on the way to the event and wanted the truck ready to drive itself if something happened on the way home.

It takes a lot of air to fill up a XZL. I was about half way done with the 4th tire when the compressor killed itself. DP had OBA on his CJ and that finished off the job.

I found another York, did the oil passage thing again and put it on the truck. While recovering my Gasser M35's it was used for hours on end. So much that the semi air brake hose melted. I then ran copper from the compressor to the tank.

At the 2008 FE in Colorado, I had tire issues. My clutch on the York started shorting out. I went through a dozen fuses that week. I fixed it once home.

Now that I have the 6.2 and 2 alternators. I removed the OBA. I am going to go with a Powertank instead. More psi, portable and multi vehicle. Less money in the long run too.

Just my lessons and suggestions.

I have seen several done with the old V style Chrysler compressors. They are two stage style and pump up fairly quickly. Unfortunately, they are also fairly large.