Craftsman mower model 917.377530, Briggs and Stratton engine model 12H802-2675-E1: I pulled this mower out of my garage for the first time in about 5 years to clean it up to sell. It worked last fine time I used it...I just replaced it with a new mower with a larger bag capacity. I added about a quarter tank of gas just to see if it would fire up, and went to get some Seafoam to add to the gas assuming the carb would be likely gummed up. When I got back to the mower, I noticed gas was dripping out of the primer bulb, apparently from a hole in the tip. I figured the bulb had dry-rotted and formed a hole. But wanting to just see if it would start, I pushed the primer bulb 3 times, covering the hole in the tip, and it started on the first pull! I let it run for only a few seconds since I'm sure it needs fresh oil.

Assuming I needed a new primer bulb, I took the cover off the carb and pulled the primer bulb out. But it appears that the hole in the bulb is by design, which I later read could be the case for a primer bulb. So my questions are, is there really supposed to be a hole in the bulb for this engine, and if the hole is supposed to be there, why does gas leak out of it? Is there a bad seal somewhere else that is providing a vent to allow it to leak from the primer bulb hole? Any ideas for what may be the problem?

Thanks for any thoughts!

Jim