I have a generator that is used for emergency power. I would like to know if it is reasonably safe to plug into the two 125V outlets, each rated at 20A and combine them into a 240V, 20A circuit to run my water well. I have previously used a long heavy-duty extension cord 12-2 w gr and plugged into the L14-30 generator output. That will soon be hooked to a transfer switch to run other circuits in the house. Since the generator transfer switch is sized to match that 30A outlet, I feel I could get more out of the 5550 gen set by leaving the water well to run on a cord. The well is usually run twice a day for an hour each time for showers, building the pressure back up in the system, and catching water for drinking, flushing, etc. Since the gen set is capable of much more than 30A, I'd like to hook the well up "as needed" through an extension cord, as previously done.

My idea is to wire two male plugs from the generator receptacles to an air conditioner disconnect rated for at least 20A at 240V, thus providing a means to assure both hot legs are activated simultaneously. Any thoughts on this are appreciated.

They would need to be on opposite phases.
I can't tell you where in the code it is not allowed, but it shouldn't.
If 1 cord came unplugged, the plugs prong would be live and be a shock hazzard, resulting in Injury and/or death, not to mention a Lawsuit.

Is the 5550 watts the running wattage or the surge output? You should have a 240 outlet. That's probably what you would connect the transfer switch to and probably the max you are going to get out of the generator.

5550 is running with 8700 surge watts. The transfer switch will hook up to it through the 30A plug. Realizing the 1st response was correct in that one unplugged connection is dangerous, I'll settle for having just 4 circuits available in addition to the water well.
Thanks, curlie.

Your much better off using the transfer switch for all connections... then if you feel that you want to shut off the pump, just switch off the breaker. Most transfer switches rated @ 30 amp 240 volts have 6 or 8 breaker spaces... (some have ten). This eliminates all but the twist in cord to the transfer switch.

Why don't you just install the correct plug on the generator. Use a box and a weatherproof cover which allows a cord to be used when plugged in at a wet location.

I don't know what kind of wiring options you might have. A crd connector and heat shrink could strain relief the wires entering thr box. Typical SO cord won't hold up because of the insulation of the inner conductors.