Walk Behind Lawn Mowers

i have just bought the basic push mower with the 149 cc Kohler engine, i followed the owners manual for start up but when I went to start it, it wouldn't start. i check the plug it is good and it seems to be getting gas, the oil is at the full mark. I tried spraying a little started fluid in it just to see if it would do anything and it started right up but it only ran till all the starter fluid ran out i was wonder if there was anything else i could check or if there was something i over looked thanks