I have a 2003 Briggs and Stratton 4.5HP lawnmower model # 10G902. We bought it 2nd hand from a repair shop a couple of months ago and it has been working fine. My boyfriend used it last week without a problem (we also leave it outside without a cover on it). This week I decided to be nice and mow the lawn for the first time and it wouldnt start. After priming it a few times it started then immediately stopped---> it did that about 3 times. Now my boyfriend blames it on me. I have emptied all the old gas, which look like it had a little h20 in it and replaced with new, changed the oil which looked black, let it sit overnight, disassembled the carburetor and cleaned it, changed the spark plug. I noticed that when I primed it--- there was only a small quart of gas coming out, is that ok? What else can it be? Please help.. Oh also, does anyone have a pic of of top of the carburetor that shows that small a black springy thing, I think I might have put it back on wrong --- Thanks