In my garage, I have a subpanel, which has the supply coming in on three black (one has white tape around it--I'm assuming this one is the neutral wire) heavy duty wires. 2 of the wires have 115VAC each. There's a grounding rod about 3 feet from the panel. A thick bare wire in a flex conduit connects the rod to the panel.

The ground wire and the neutral wire both connect to the neutral bar in the panel box.

My question: Can I wire a 220VAC outlet from this configuration? If so, how can I do it?

I want to run a 2HP pool pump and motor. The motor is rated 220VAC, 10amps.

If this is indeed a subpanel, then the ground and neutral need to be separate. Usually a ground bar kit is required. So that needs to be fixed.

When you purchase a 240 GFCI breaker, you will get two points to wire to. This breaker will probably trip with the box in this configuration. There is a load neutral (not used in your configuration) and a neutral to the breaker.

Use UF cable buried at least 18" deep. You can use 14 AWG cable anda 15 A breaker. Tape the white wire red.

If this is a detached garage the grounds and neutral are not kept separate when a 3-wire feeder is used. The 2008 NEC removed the allowance for 3-wire feeders, but that is irrelevant in this case.

I have to honestly say, if you do not even know the basics of wiring a 240v circuit you REALLY should not be messing with pool wiring.
There are MANY important codes regrading pools and this is NOT the place you want to mess up or do something wrong.
One of the main rules is NO UF cable for ANY of the outdoor portion of wiring for pool equipment. You must use conduit with an insulated green ground.

If this is a detached garage the grounds and neutral are not kept separate when a 3-wire feeder is used. The 2008 NEC removed the allowance for 3-wire feeders, but that is irrelevant in this case.

I have to honestly say, if you do not even know the basics of wiring a 240v circuit you REALLY should not be messing with pool wiring.
There are MANY important codes regrading pools and this is NOT the place you want to mess up or do something wrong.
One of the main rules is NO UF cable for ANY of the outdoor portion of wiring for pool equipment. You must use conduit with an insulated green ground.

This is a detached garage. I do have a basic understanding of electricity but have not worked with 220VAC.

My previous motor was 120VAC and this new one is 220VAC and was wondering if, with my current configuration, it could be done.

Having a basic understanding, and wiring up pool equipment, is quite a separation.

What Stan is leading to, the panel neutral and grounding is one issue, minor compare to pool wiring.

If this is a metal pool, or with any metal parts, such as ladders, diving boards, handrails, metal mesh in concrete, etc, any metal within 5 feet of the pool wall must be bonded back to the grounding lug on the pump motor using a bare SOLID # 8 copper wire.

There are other various rules,such as, that different between in ground pools and above ground pools, required general purpose outlet locations, disconnect locations, dealing with light fixtures, etc.

You should review the sticky at the top of this forum, contains a link to review the NFPA 70: National Electrical Code® (http://www.nfpa.org/aboutthecodes/AboutTheCodes.asp?DocNum=70&cookie_test=1), and review Article 680.

And local codes must be followed also, every town or state I wired a pool had specific details an requirements. You have applied for a permit to wire this pool, correct? You will discover what those requirements are when you apply for the permit.

I did pick up on if you had a basic understanding of electricity, you would know that plugging in a 2 pole 240 volt breaker into a standard panelboard, you would automatically have begun your 240 volt circuit.