I just hauled home a used compressor and need to know what I need to do the wire up the beast. It is a 220v and it says 15 amp on it. I have what looks like a 220 15a breaker running to what looks like a 220 outlet in my garage. I enclosed some pics. I also need to know how to wire a plug onto the compressor wire to use the plug on the wall if possable. The wiring on the compressor has 4 wires and the plug has 3. The 50 amp circuit coming out of the breaker box is running my hot tub. Any help is appreciated.
http://i88.photobucket.com/albums/k171/carguy00/Wiring/pics015.jpg
http://i88.photobucket.com/albums/k171/carguy00/Wiring/pics016.jpg
http://i88.photobucket.com/albums/k171/carguy00/Wiring/pics018.jpg
http://i88.photobucket.com/albums/k171/carguy00/Wiring/pics019.jpg

Red to one side of the outlet and black to the other side, white to center ground terminal (probably)
Only three conductors needed, so the bare graound may be the one to the center terminal.
You can look inside the motor's J-box and see.

That black cord shown has a 120 volt plug, you'll need a plug that matches the outlet.

I don't see a double pole breaker in the panel feeding the outlet.

Would i run the white and bare wire together?

You could but not necessary.
A white wire is not needed for a 240 volt circuit BUT many times a white is used for the ground, usually because there isn't both in the cable so no bare wire.

I don't see a double pole breaker in the panel feeding the outlet.

I see two double pole and two single pole. If you look closely the two double pole breakers are single switch just not double switch. I have a few of these my self. The top left and bottom left are the two double pole (220V) circuit breakers.

Some codes require 240v systems to have two hots, a neutral and a ground. You can find a 4 prong plug at your local electrical supplier or hardware store, make sure it is rated for your current use. If you decide to use four wire, you will have to make a new run and a new outlet that accomodates a 4 wire system. That said if you decide to get a matching plug for the existing socket, just abandon the white wire, and connect the ground to the correct pole on the plug. Make sure you check to see if the socket is connected the same way.

The neutral (white) (grounded conductor) is never needed on a straight 240 volt circuit, it's only needed if there is also a 120 volt load involved, such as a motor, timer or clock.
Like I said, many times the white is used as a non current carrying case ground on a 240 volt circuit just because it's what's in the cable such as 10/3 without ground NM.

Go to this site and learn about load bearing circuits: http://www.make-my-own-house.com/electrical-wiring-diagrams.html

The white will run from the neutral buss bar to the recepticle . Red wil run to L1, black to L2. bare copper to the junction box. And please turn off the power, 220 V will kick you hard.

I opened the box on the compressor and the bare ground was not used. The big white was used as the ground. I am going to get rid of the recepticle on thee wall all together and run the wires in direct to the compressor. There are 3 wires running to it so it looks like I will use the bare as the ground. I'll let you know if I see any sparks. I need to run to the hardware store for some plumming first. The petcock on the botom of the tank was srtipped so I had to remove it to got the water out that looked like it had never been drained. I got out about a gallon and a half of water. I am going to install a ball valve down there to make it easier to drain in the future. Also need some fittings the get me drier on. Oh ya I also broke the aluminum line that runs from the compressor to the tank at the fitting so I have to cut a 1/2 inch off that anf get a new compression fitting. Thing are going from bad to worse so far.

If the previous person used the white wire as the ground, you can continue to use it as such.

The white will run from the neutral buss bar to the recepticle . Red wil run to L1, black to L2. bare copper to the junction box. And please turn off the power, 220 V will kick you hard.
That is wrong.

Again, NO conductor will connect to the neutral bar since NO neutral will be used.
The white wire is not really a "white" (neutral) wire, it is kept isolated from the neutral bar in the sub panel and connected only to the ground terminal.
I think people get confused when they see any color insulated wire being used as a "bare" wire as a matter of convenience.

There are four conductors feeding that sub panel as there should be but only three are needed for older straight 240 volt circuits, two hots and one ground.
I opened the box on the compressor and the bare ground was not used. The big white was used as the ground. I am going to get rid of the recepticle on thee wall all together and run the wires in direct to the compressor. There are 3 wires running to it so it looks like I will use the bare as the ground.
That will work since the bare wire and the white wire both go to the same ground terminal in the motor but I would use the White as the ground myself.
Might as well use the heavier-insulated wire for the ground since it's there.

Dean, I am not going to use the wires in the pic. I disconnected them from the compressor. I also disconnected the 3 wires from the outlet in the pic. There is a white, black and a bare running from the breaker box. If I am looking at it right I will use the black and the white as the 2 hot leads and use the bare one as the ground as that is where it is in the breaker box.

if it was a hot tub .....I'd say the white was a neutral the bare copper was ground , red & black 110v hot ...
which means I agree with Dean

I don't know of any reason for a separate neutral on a compressor unless they were running a 110v fan for a condenser

Dean, I am not going to use the wires in the pic. I disconnected them from the compressor. I also disconnected the 3 wires from the outlet in the pic. There is a white, black and a bare running from the breaker box. If I am looking at it right I will use the black and the white as the 2 hot leads and use the bare one as the ground as that is where it is in the breaker box.

Thats correct.
As pictured, the white coming from the panel is one of the hots.
I said "terminal in the sub panel" when I meant terminal in the motor"

white from panel =hot
white from motor = ground.

The white is never supposed to be used as a hot, and is really against code. If for some reason you do use it, at least color the wire at both ends (like some black electrical tape) so the next guy whoever works on it will know its a hot and not a neutral.