Small Engines (Lawn Mowers, etc.): Murray 309000x8B wont start, gas oil, armature

Question
Murray 309000x8B will turn over and has spark but will not start. Engine is B&G 28R707-1120-E1.

A little background is the wife put in my weed-eater gas/oil mix and mowed half the lawn and it died. I drained the gas, put in fresh gas and it turned over but it would not start (hope I'm saying that right) and had no spark. A friend helped troubleshoot and narrowed the problem down to the armature which we replaced. Now we have spark but it will still not start.

Thanks for any help!

Answer
The gas oil mix will not hurt your engine, maybe foul a spark plug but thats it.  Do you have compression?  Is the fuel getting to the carb?  Take a can of carb cleaner, remove the air filter cover and see if the engine starts and then dies.  If it does its simply a problem with the fuel not getting to the cylinder.

HTH