fuel problems

I recently overhauled the 4 cyl engine in my 86 fiero, and had it running good. For some reason the battery drained, so I took it out to recharge it, and reinstalled it. When I tried to start it, after I cranked the engine for about 5 seconds, I heard a muffled pop or snap, and now it won' :screwy: t start. I checked the spark, and there is a real strong blue spark, so it must be the fuel. Any one have any ideas what it could be?