10-19-10 Shadofax belt driven OBA (not York)
This will be a full on writeup over several months/most of winter that I hope spurs interest in alternatives to a York belt driven setup, if someone happens to want to look for something different as I have for years. This is also a belt driven setup, so if you are thinking high-amp electrical compressor (Oasis) or something like CO2, this is not the place. I can tell you I explored all those options, and without a doubt it's the belt driven's sheer air power supremecy and underhood stealth I've always wanted.
With the intro., I'm not knocking a york setup. The 210 is king of CFM output in my understanding, and the whole system can be fairly cheap if buying a used York210 that works from a JYard. It's just that the separate v belt setup headache (the pulley/bracket stuff is not that cheap either), and it's size/weight, and it gets in the way, and the whole oiling mess and extra hosing/connections just kept me from going this route all these years. To be honest I've kept my stock AC sitting and waiting for the day I'd re-install for OBA. But I still had that oiling mess setup.....
Until now. PAUSE for one important point so you don't have to go too far in reading if you don't have the space
. The unit I will be discussing is ideal for me because it is the exact size of the stock AC compressor I removed and in my install is meant to EXACTLY go back in place of it and look just like a totally stock AC unit, you'd have to double take to realize that is my OBA. Not to say you can't work up something else, but this is truly a stealth/stock location setup for those willing to give up their AC.
While shopping on-line a couple months back I stumbled on this unit while once again trying to justify Co2 or better yet a monster electrical compressor so that I'd finally stop using my ARB underhood compressor (for my front locker) as a tire fillup station (37" tires). Anyway, I found a monster of an electrical, but at $545 and 2.6cfm at 100psi and a whopping 95Amp draw, I shuddered (the oasis does more CFM but the amp draw is basically like a winch at light load, 175amp). These units are also very large (could not fathom where it would mount under my hood), and the Oasis weighs more than a York.
So back to the on-line shopping site, their top o the line baby happened to be a belt driven AC compressor, brand new and $410. 8 cfm at 100psi, capable of up to 200psi. Ater questioning the belt driven rpm I was told this unit will do 800rpm (assuming crank and compressor pulley are equal) idle and produce 3.2cfm. Bump to 1300rpm and you could see a little over 5cfm. The york210 I've seen several figures but I believe the accurate one is that it can do 4cfm at the same 800rpm. This is substantial if you know 120/210v compressors, it's probably equivalent to a 4 HP motor driving those and will drive a good portion of the air tools out there, especially with a tank reserve.
So anyway, I am just beginning this project, I can tell you this is not the cheap alternative, but in the end, if you want:
1) The best OBA alternative that you don't have to refill at a gas place, that is hidden, and that can produce great CFM's like the York belt driven
2) That does not suck massive Amps to produce air and is compact and LIGHTWEIGHT
3) and if you've looked at the yorks, but which one, how to tell? How to rig up the pulley, and all the oiling lines and stuff and fab just not your thing? And the added hefty weight and getting in the way of everything
4) and you don't mind losing (or have unworking or have already pulled) your stock AC
5) and you want simple underhood, powerful, clean/stock look, stock belt, no mess, no fuss
This is a writeup to possibly follow
On to some beginning pics as I now have the items ordered at the house....
This is where my stock AC used to reside, drivers side, currently there is just this ford dead pulley if you don't have AC:
So this pic is pretty much what I bought online. I will still need misc. 1/4" NPT fittings and 3/8ths hose etc. but that will be local. My '95/351 factory AC compressor is on the left, new OBA compressor on right, both serpentine (though the OBA is capable of 10rib, more on that later). Actually I won't tell you all the pieces here as I think I will put them in a shopping list later. Aren't those compressors very similar though? Should be an easy fab to get the new one to fit perfect.
Overhead view, both serpentine pulleys happen to be the exact same diameter, so as long as I fab a simple mount to place the new compressor in the stock location, there is no cost of a new belt, nothing, ready to go with stock belt. size of compressors and mount tabs are very similar, so this should be fairly easy, and once I've done this it can be duplicated. Also note what's on top of the new compressor, is that a zerk????? Why yes it is. Requirement is redline grease only apx. 4month interval under normal 4wd use.
last pic for now is more about the tank, it's 8"x about 17.5" so while it's stated at 4gallon, I view it as about 3.75 gal. based on the cylinder volume calculation, but whatever. It has ports, will fit above the rear driveshaft in that nice space, holds 150psi as a safe/approved pressure, painted inside/out and DOT approved. This will hold down on compressor cycling as the pressure switch is set for 145psi max/110min. I'll regulate the output of the tank to like 95-100psi. I have a blowoff valve pictured earlier that is for 165psi (the tank is actually rated for rupture above 700psi)
Stock AC compressor is about 15lbs, new unit about 17lbs, and york I believe is 45-50lbs, an oasis more like 65lbs. My next steps are fabbing a simple mount, removing the dead pulley and installing the compressor for now. As long as clutch is not engaged it just free sprins. pics for that step coming....