Darned lawnmower won't start!
Of course, I waited too long to mow my lawn. It was getting so high I feared the city would complain, so I waited for a cool dry evening and dragged out my trusty Troy-Bilt push mower with the Briggs and Stratton 675 Series engine. I made one lap around the lawn when the thing died. It had very little gas, so I refilled it. No dice—it would start for one or two seconds, then die, over and over again. After enough attempts, it began to not start at all unless I left it alone for several hours, then it would again start for a couple seconds, then die, and then refuse to start at all for several more hours. What to do? The grass is getting higher!
I tried several resources to get this thing fixed. I bought the Haynes Small Engine Repair manual (from 1990, no less); no help. It suggested several things that did not seem directly related to my problem. I went to the Briggs and Stratton FAQ; it suggested that the problem was stale gas. The gas I was using was left over from last season; apparently that's not okay. So I bought a siphon, emptied the fuel in the tank, and filled it with fresh gasoline I bought that day. No luck, even after many pulls and leaving it overnight. In desperation, I turn to the Internet again. I had read somewhere (the Briggs and Stratton site?) that cleaning the nozzles at the bottom of the carburetor could solve this problem. I followed this Guide to disassemble the carburetor to get to those nozzles, cleaned them with carburetor cleaner, and it started up and ran like a dream!
Make sure you clamp the fuel line before taking the carburetor apart! Otherwise you will get fuel everywhere. Luckily another site informed me of this. Also, make sure you clean the nozzles in the screw that comes off the bottom of the carburetor—that's what actually needs cleaned, more than the float tank itself.