I just finished setting up my Homelite 2500 and turned it on. Once running to 30 seconds it let out a loud pop they scared the hell out fo me. I truned off imdeiately in fear of ruining the engine. Any advice as to what might have caused this? It was a loud bang

Buck up now. You did good turning it off. Check the oil and water as described below and then fire it up again.

The power washer is your friend, but do NOT wash off your shoes while wearing them. Or rinse your dog or your hand >> it will blow a hole in aforementioned.

1) Your water has to be turned on before firing up the pressure washer. Simply squeeze gun trigger while starting engine. Do NOT wire the trigger closed to start or use power washer wand. That is a good way for the thing to break free and punch a hole in your pants.
2) You need oil in engine and in pump > engine oil comes about half way up dip stick > pump oil comes up to middle of viewing window on pump head.

That's all there is to know. I think your new engine had a growing pain, and things are fine.

Honda is a good engine. We ran our first Honda power washer for years until it fell off the trailer upside down and the chain kept it tied to the trailer until the gas tank was sanded off by the freeway after which it caught fire for a bit. You will have better luck.