Quick help with a regulator?

So I bought a regulator off ebay and it seems completely defective. I have built many people kegerators over the last 2 years and so this is the 6th I have bought and never seen anything like this. I know one of you can help me! When I hook it up to the CO2 tank and turn the gas on it comes screaming out of the pinhole that can be seen when looking right at the screws from the front. The only difference that I can see from this reg and my other one that I have in front of me is that the defective reg’s pinhole is in a different location. When I say different location, I mean that my working reg’s pinhole lines up with the air line OUT quadrant of the reg, this defective one’s pinhole lines up with the metal shaft that connects to the CO2 tank. I have never opened up a regulator by taking out the four screws in the front to examine the diaphram? Can I screw this reg up any further by doing this? Part of me wants to send this thing right back to the seller, but I will probably be out the return shipping costs, the other part of me doesn’t mind fixing and keeping it if it’s an easy fix. Help?

Sounds like it is leaking past diaphragm. Either it has a hole in it or someone tried to replace it and installed it improperly. Take four screws out and inspect.

Also the vent-hole can be in any one of four positions depending on how cover is put back on. It does not align with anything.

You might also look on the back to see if the ports are marked. HP/LP, in/out. I found a brand new reg. (Harris) at work that was assembled incorrectly.

Ok, so I dug into this thing. I was a little apprehensive, but clearly there isn’t much going on inside of one of these things so it was no big deal. So here are two more pictures, which way is the diaphram suppossed to seat in here. When I opened it, it was placed like it is in the first picture. Should it be flipped over and done the other way, like in the second pic? Also, all my Hi and Lo’s are in correct order, so rule that out.

So I just went to cornelius’ official website and looked at a diagram. I believe I have answered my own question. Thank you to the two replies that I received, I can always count on this forum!