I spoke with a friend of mine who installs pumps and drills wells. He said it is best on the pump to let it run for long periods of time vs. having it cycle on and off too much.

His other suggestion was to put a fan behind the pump to blow the heat away in order to keep it cooler.

When I filled my pool I let it run for periods of about 4-6 hours overnight. I used two hoses each from a different faucet and this kept the pump running continiously.