I purchased a slightly used B&S 675ex that did not run (I knew this). I've begun tinkering with it to see if I could get it to start. So far, I have checked the spark plug, fuel and oil levels and they seem to be good. I checkled the carb and cleaned it. It had some gunk inside and the bowl seal needs replacing. Once everything was inspected and cleaned I tried to start her up and she ran for a few seconds before quitting on me. Now it won't start up at all. I have now noticed fuel leaking through the air intake/choke. Could this be the reason why it won't start anymore? If not I don't know what else to look for. Any help is appreciated!