I had a chance today to open up the compressor and give it a test run. First up a shot of the package. The UPS billed weight on this thing was 23lbs, it's quite the brute. I'm not sure what the ARB unit weighs, but this thing is like carrying a small child around.
Once you open the box you're greeted by a styrofoam clam shell that houses a black nylon bag. The pull on the zipper of the bag had already broken off inside the styrofoam, not a good omen. Before anyone asks, no the bag is not of good quality. You could buy a clearance lunch box from the dollar store and get a better quality container than this bag. Oh well, I didn't buy it for the bag.
Inside the bag is obviously the compressor and it's accessories. You get the manual, a hose with a proprietary connection on one end and the inflating tip on the other and three attachments.
Integrated into the hose is a pressure gauge, we'll give this a try in a few minutes and see how accurate it is.
Some specs from the manual. The duty cycle is listed here but I don't recall seeing it on the website.
Time to take it out and try inflating a tire! The clamps that are hard wired onto the compressor are small to say the least. They barely fit over the posts on my Tacoma's battery and on the positive side I had to connect it to one of the bolts on the connector. The wire is an ok gauge I suppose, but moving to some better wiring would probably cut down on some resistance. I may rewire it in the future.
I took a read of the tire pressure using a gauge I knew was accurate after dropping the pressure to about 18psi (33 inch tire). I then connected the compressor and checked the reading on it's gauge. Hmmm...just a little (7 psi) off.
So from 18psi I took the tire back up to 32 psi. This is one of the tires on my M101A2 trailer and this is the pressure I normally run them at. At exactly the 1 minute mark the tire was back to 32psi. Not too bad I guess. The compressor itself wasn't even warm after this 1 minute inflation, although the hose and the fitting it connects to on the compressor were a little warm.
From here I figured I'd break into the compressor a bit and check the build quality. First I removed the small cap holding in the "filter". This is a bit of a joke, but I suppose with some care it'll work to keep things out of the compressor. There's a small foam filter element on top of a small felt ring. What's the felt for? I have no idea. Perhaps they ordered 200,000 of the foam elements that were too short and it's there as a spacer? Not sure.
After pulling the foam filter and the felt pad you can see that the filter housing is just a round plastic clip that is screwed directly into the top of the housing using three small machine screws.
Flipping the housing over reveals that these machine screws were just run right down into the intake side of the housing. Why not create some stand offs or cast a small protrusion that would be tapped to accept these screws? Because this is probably cheaper. If they start to back out or vibrate loose I suppose I'll find a better way to secure them in place.
Here you can see the reed valves for the exhaust (or supply) side of things. These screws are inserted into a tapped opening and the reed valves seem like they're ok quality. If they did fail for some reason the end of an old feeler gauge would probably make a good replacement.
Here are the valves for the intake side of things along with the cheap rubber ring that's sealing the entire thing up.
Here's an overhead of the piston, notice that the heatsink fins only come in contact with the cylinder in 4 places. The MV50's and 90's are designed this same way but I can't help but wonder if a coating of thermal paste to fill in that air gap would help things run cooler?
A couple more shots of the filter housing and screws along with a shot of the compressor next to some pliers for scale.
My initial impression is that this seems to be a notch above the MV50's and MV90's that are out there. I've never seen a tear down of the smittybilt compressor so I'm not sure how this compares. The piston and sleeve in this unit seem (at least visually) to be made of better materials, there's not as much pitting or poor quality metals. The filter elements are a bit of a joke and I may try using something different...cutting some universal lawnmower type filter pads may work.
The hose and it's gauge are a joke but I'm not sure what the thread size is on the proprietary connection to the head of the unit. Once I figure out if it's 1/4 NPT or not I'll see if I can't get some sort of standard quick disconnect in place.
I'm trying to decide if I'm going to mount and hard wire this in somewhere on the truck and if I'm going to add a tank or not. For the next month or so I'm just going to stow it behind my rear seat and use it. I'll keep this thread up to date as I progress.