The generator will simply act as an idler if no wires are connected to it. You'll need a well-charged battery, and some way to keep the engine cool such as a garden hose adapted to the water pump inlet. Actually, if you don't have a radiator connected, the generator and water pump don't need to run at all. The engine can be run for quite a while with a slow, steady flow of water running into the water pump inlet and out of the thermostat housing without the water pump turning. Be sure to remove the thermostat first, however.
Jerry
