T.O'Brien

Hey,

Just wanted to share some photo's and info on my On Board Air install. This is my first major addition to the truck in the last four years of ownership besides a wheel and tire package a few months ago when I needed new tires.

I must first apologize for the photo links instead of the actual photos as with my new laptop I have yet to find out if I have any photo editing software to re-size my pics. All of the photo's and a few more can be found here: http://gallery.me.com/t.obrien#10006...lack&view=grid I will only be selecting a few of the photo's to post here in this thread. As I build and complete this project I will be adding all project pics here.

For my compressor I will be using a Mercedes-Benz Airmatic suspension compressor. The pump is designed as a constant (100%) duty pump for Mercedes S class cars. It's "normal" operating pressure range is 6-10 bar (87.02-145.04psi) It can however pump up to 13-16 bar (188.55-232.06psi at sea level). Well...so says Mercedes. I visited the Stealership in West Covina, CA early last week and a service tech provided me this information in a print-out. The tech also stated that the factory power plug to the motor's pump is known to overheat and fry, this made sense since trying to check the operation of the pump before visiting the dealership a couple of days earlier. Hense, I just cut the factory plug off, and away she blew...the compressor that is. The compressor has an attached dryer unit, which I found out while taking apart the pump to clean and inspect it, my father turned the dryer upside down on our carpet and out came all the desiccant. After arguing who was going to clean it up, I was sifting desiccant out of the shop-vac and through an oil funnel back into it's rightful place.

Now, where to mount it? after a few days of staring at the truck scratching what little hair I keep on my head, I decided to mount the compressor on the driver's side of the bed, right behind the cab. There is some factory bracing for the bed that I was able to utilize to tuck the compressor up nice and tight under the bed above my exhaust. Here are a few pictures of the Brackets I fabled up (easy enough), and where the pump lies under the truck for the time being.

Here is a pic from next to the gas tank looking towards the front left side of the bed.
http://gallery.me.com/t.obrien#10006...&bgcolor=black

Here is a shot of the pump mounted under the bed with the air inlet hose running up an open area between the inner and outer skins of the bed, there in the front bed corner on the driver side.


Here are the brackets near the compressor outlet. Just below the Grey hole is the 1/8" threaded outlet. I will be installing a check valve in that hole, then a 1/8" to 1/4" adapter and running 1/4" hose straight to the tank. Remember I don't need a water trap between the pump and tank because there is one already installed


Here is the bracket/mount just below the compressor piston and inlet area. I used rubber bushing to keep down both vibration and noise.


What about a tank you may ask?...
Well the tank I have is aluminum. It was made for a rail/train project and has been hydrostatic @ 225psi. It has a burst strength of about 1,800psi. I'ts semi-polished and has two 3/4" ports on either end (in/out) and a 1/4" center offset drain plug. Once again I was perplexed for quite some time on where I was going to mount the tank. I thought of mounting it where the compressor is now (under the front left side of the bed above the exhaust). There was plenty of clearance away from the exhaust at no less than 6" away, so there would be no heat issues. Mouning it proved to be a bit difficult because the tank had no brackets or feet to use. I was forced to find some way to strap it to the underside of the truck. Well that proved to be a bit more difficult than I thought it would be, well because I was starting to be a bit frustrated and the impatience was growing on not being able to securely strap it into its location. Back to the drawing board...

With the tank resting in the bed of the truck, it dawned on me. Why don't I just mount it in the bed? WOW!! great idea hahaha. On the right side of the bed between the tailgate and the wheel well, I have a small army storage box, locked and bolted down with jumper cables, those large 30min road flares, a folding shovel, and other odds and ends for any roadside or small off-road emergencies. The box does not stick out any further than the wheel well and allows me to temporarily stuff my Hi-Lift between it and the bedside.

Anyways, back to the tank. It is mounted on the left side of the bed directly opposite the box and does not stick out past the wheel well. Insert Photo:


I strapped it down between those bumps in the bed so it wouldn't rock back and forth.


The straps are actually threaded steel bar that I found in the hardware isle at Lowe's. I then visited the plumbing isle to see what I could find to cover the threads when I wrapped the bars around the tank, well cause I didn't want to scratch the tank. I found some sort of PVC tube or hose used for refrigerator water I think. I used standard 5/16"-24 threaded rod, covered it in the hose, and bent it around the tank. I then drilled holes in the bed, pushed the rods through, and tightened everything down. Oh, wait...the drain plug...I drilled another hole and enlarged it with a unibit so the drain hole bung would fit through the bed and fit nice and flush. Oh I did some math and the tank is 3.67 gal.

You can see my harbor freight rock light/reverse light back there too.





In total I spent $147 on eBay including shipping for the compressor and tank. The guy I bought it from used it on his K5 Blazer for a while. I'm told it will pump to 180psi quite quickly, I guess we'll see. Stay tuned for the next couple of weeks as I get my airlines, fittings, wiring, and all the loose ends complete. Please give me any feedback, questions, comments, or anything that may help out my installation from your guys, and possible gals experiences.

Thanks !!